I would consider this one a pretty weak option though, as weapon master remains a terrible feat.
the dwarf and elf options make sense. Anything else?
D&D 5E Comparing Monk DPR
the dwarf and elf options make sense. Anything else?
Curiosity got the better of me and I tried my hand at some DPR math. It includes the crit chance, but I didn't do two-weapon fighting for the rogue and I hadn't figured out how to add Advantage yet (in the case of Steady Aim).
Rogue 15
+1 dagger, +11 to hit, 1d4+6+8d6 avg. 27.375
+3 rapier, +13 to hit, 1d8+8+8d6 avg. 34.425
Monk 15
Staff of Striking +13,+13 to hit, 1d8+8 avg. 21.25
w/ Unarmed +10 to hit, 1d8+5 avg. (7.6) 28.85
w/ Flurry +10, +10 to hit, 1d8+5 avg. (15.2) 36.45
The monk is definitely doing well compared to a rogue with an inferior weapon, but that isn't really very impressive. So I also included a line with the rogue using a +3 rapier. Compared to that the monk only surpasses it by using Flurry of Blows. I will also restate as others have that the monk can move some of his damage to another target if their current target drops, whereas the Rogue just wastes their damage on overkill. This is also just using Flurry of Blows. If the monk can land a Stunning Strike his DPS jumps massively.
Speaking of Stunning Strike. When ever it is mentioned as being crowd control the caster with Hypnotic Pattern is mentioned. So I went ahead and calculated the DPS of a Wizard using Hypnotic Pattern.
Wizard 15 w/ Hypnotic Pattern DPS avg. 0
Wow! Look at that! The monk just blows him out of the water on DPS.
I would also like to mention that while the monk can stun 1 creature per hit, the rogue stuns 0. So the monk wins there as well. 
Asisreo
Patron Badass
I apologize. I meant that a +1 dagger on a monk exceeds the average damage of a nonmagical quarterstaff at levels 15+. Meaning that magical items that would be clearly "inferior" gain alot of mileage off of monks.Curiosity got the better of me and I tried my hand at some DPR math. It includes the crit chance, but I didn't do two-weapon fighting for the rogue and I hadn't figured out how to add Advantage yet (in the case of Steady Aim).
Rogue 15
+1 dagger, +11 to hit, 1d4+6+8d6 avg. 27.375
+3 rapier, +13 to hit, 1d8+8+8d6 avg. 34.425
Monk 15
Staff of Striking +13,+13 to hit, 1d8+8 avg. 21.25
w/ Unarmed +10 to hit, 1d8+5 avg. (7.6) 28.85
w/ Flurry +10, +10 to hit, 1d8+5 avg. (15.2) 36.45
The monk is definitely doing well compared to a rogue with an inferior weapon, but that isn't really very impressive. So I also included a line with the rogue using a +3 rapier. Compared to that the monk only surpasses it by using Flurry of Blows. I will also restate as others have that the monk can move some of his damage to another target if their current target drops, whereas the Rogue just wastes their damage on overkill. This is also just using Flurry of Blows. If the monk can land a Stunning Strike his DPS jumps massively.
Speaking of Stunning Strike. When ever it is mentioned as being crowd control the caster with Hypnotic Pattern is mentioned. So I went ahead and calculated the DPS of a Wizard using Hypnotic Pattern.
Wizard 15 w/ Hypnotic Pattern DPS avg. 0
Wow! Look at that! The monk just blows him out of the water on DPS.
This includes weapons like Dagger of Venom, Berserker Handaxes, Javelin of Lightning, Mace of Disruption, Mace of Smiting, Mace of Terror, Vicious Daggers. Also every single "random sword-type" magic item can also be used with monks in the form of shortswords. So monks yield more damage from a shortsword defender than a Paladin would.
doctorbadwolf
Heretic of The Seventh Circle
Edit: for clarity, the monk benefits more than most from things that increase the impact of a crit, and things that just make every single attack better.
What is the most reliable source of;
Increased crit damage and/or chance to crit? So, reliable advantage, increased crit range, items that deal more damage when you crit, etc?
and
Extra damage per attack, per damage roll, etc.?
Because it's really easy to get a use of hex or hunter's mark with a feat, but that's once per day. MC Paladin (Vengeance) is three levels of a class that has a major stat that the monk doesn't, but it does get you spell slots, smite, and oath of emnity. Cha 13 isn't hard to do if you roll stats, but otherwise trying to have even non-dumped cha on top of good dex, wis, and reasonable con, is...rough. 1 level of Hexblade gets 1/SR extra damage per attack and better crit range, but still suffers the MAD problem. I don't really know about clerics or druids, do they have any low level feature options that would add to the Monk's per attack damage and/or increase crit frequency?
Fighter is a really good MC for Monks, with a few really good ways to go. BM lets you choose to use a SD when you hit, which makes each hit count more, and Champion gives you the expanded crit range, while level 1 and 2 is just really good for fighter.
Is there something missing here that could be a feat that would help the monk, but not be OP for other classes?
What is the most reliable source of;
Increased crit damage and/or chance to crit? So, reliable advantage, increased crit range, items that deal more damage when you crit, etc?
and
Extra damage per attack, per damage roll, etc.?
Because it's really easy to get a use of hex or hunter's mark with a feat, but that's once per day. MC Paladin (Vengeance) is three levels of a class that has a major stat that the monk doesn't, but it does get you spell slots, smite, and oath of emnity. Cha 13 isn't hard to do if you roll stats, but otherwise trying to have even non-dumped cha on top of good dex, wis, and reasonable con, is...rough. 1 level of Hexblade gets 1/SR extra damage per attack and better crit range, but still suffers the MAD problem. I don't really know about clerics or druids, do they have any low level feature options that would add to the Monk's per attack damage and/or increase crit frequency?
Fighter is a really good MC for Monks, with a few really good ways to go. BM lets you choose to use a SD when you hit, which makes each hit count more, and Champion gives you the expanded crit range, while level 1 and 2 is just really good for fighter.
Is there something missing here that could be a feat that would help the monk, but not be OP for other classes?
One of the problems a monk has is that the Martial Arts attack or Flurry of Blows must be unarmed attacks. So no matter how awesome the weapon you have, you don't get the benefit of it other than the two you get with Extra Attack at 5th level. Something like Hex and Hunter's Mark would be great, but they are difficult to get. I don't think spells like Holy Weapon work as it has to be cast on a weapon and I don't think the monk's fists count.
The more I think about it the more I agree with a previous poster (I might go back through the thread later to give proper credit) that there should be some improvements to the Ki Features at 11th level. I would go with the following:
Improved Ki Features
Starting at 11th level your ki features gain the following improvements:
Flurry of Blows
Immediately after you take the Attack action on your turn, you can spend 1 ki point to make three unarmed strikes as a bonus action.
Patient Defense
You can now spend 1 ki point and use your reaction to take the Dodge action.
Step of the Wind
You can now spend 1 ki point to take both the Disengage and Dash action as a bonus actin on your turn, and your jump distance is tripled for the turn.
The more I think about it the more I agree with a previous poster (I might go back through the thread later to give proper credit) that there should be some improvements to the Ki Features at 11th level. I would go with the following:
Improved Ki Features
Starting at 11th level your ki features gain the following improvements:
Flurry of Blows
Immediately after you take the Attack action on your turn, you can spend 1 ki point to make three unarmed strikes as a bonus action.
Patient Defense
You can now spend 1 ki point and use your reaction to take the Dodge action.
Step of the Wind
You can now spend 1 ki point to take both the Disengage and Dash action as a bonus actin on your turn, and your jump distance is tripled for the turn.
fearsomepirate
Hero
With a magic weapon, the monk's base attack is pretty close to a rogue's, even without doing anything cute to get a battleaxe. It does fall behind at around 11th level, but by that point, you can use Stunning Strike and Flurry of Blows a lot more often.
I'm so far unconvinced that monks have a damage problem. I think it's more that in rounds where their SS fails and they end up using their bonus action to avoid getting hit, they're almost as anemic that round as a wizard who just cast as a failed SoS spell. I noticed that the Way of Shadows monk in our campaign would have some really weak rounds...on the other hand, the sheer amount of pain a successful Stunning Strike unleashed more than made up for it IMO.
doctorbadwolf
Heretic of The Seventh Circle
I think I and other poster suggested this sort of thing. I’d definitely go for it.
Asisreo
Patron Badass
Is this a problem? Or an inconvenience?
A problem would mean that because they don't get to add a bonus to their flurry, something goes wrong. But as far as I know, nothing breaks. It would be a problem if holding a magic weapon meant you couldn't use Flurry of Blows at all which would mean there are no benefits to magic items for damage.
Really, all that means is instead of your +2 dagger doing +8 damage with flurry of blows, it just does +4 as normal. But your flurry didn't get worse and neither did your extra attack.
Hmmm... I guess it would be a... limitation? It means that a monk gets no more benefit from a magic weapon than a barbarian, paladin or ranger and they all get less benefit than the fighter. They all get two attacks with their magic weapon. After 11th level the fighter gets more.
After giving it some thought, I have revised my improved ki feature abilities. The Flurry of Blows is fine. It adds an extra unarmed strike, but it doesn't overshadow the fighter because you still have to spend ki to get the extra attack and it has to be an unarmed strike, which, as has been discussed, is generally weaker than an extra weapon attack. Being able to use Patient Defense as a reaction overshadowed Deflect Missiles and prevents the monk from making an opportunity attack, which I think actually makes them less useful. So instead I just added an AC bonus to the ability. Finally allowing Step of the Wind to give both the Disengage and Dash actions, plus tripling your jump distance is a pretty good upgrade since by 11th level the monk will be moving ~50' with a single move and can run along walls and over water. Disengage makes you immune to opportunity attacks for the turn, which allows the monk to move right past enemies without having to swing wide to get around them. So the final abilities (for my house rules) look like this:
Flurry of Blows
Immediately after you take the Attack action on your turn, you can spend 1 ki point to make two unarmed strikes as a bonus action. At 11th level you can make three unarmed strikes as a bonus action instead of two.
Patient Defense
You can spend 1 ki point to take the Dodge action as a bonus action on your turn. At 11th level you also gain a +3 bonus to your armor class until the beginning of your next turn.
Step of the Wind
You can spend 1 ki point to take the Disengage or Dash action as a bonus action on your turn, and your jump distance is doubled for the turn. At 11th level you can take both the Disengage and Dash action as a bonus action on your turn, and your jump distance is tripled for the turn.
Asisreo
Patron Badass
I'd say PD should probably only have a +1 AC boost since Dodge is already one of the strongest defensive buffs in the game.
Really, with +3 AC and Dodge, there'd be no reason to ever use Step of the Wind outside of niche kiting scenarios which probably can be done otherwise.
If I had those features, I'd do this: Stunning Strike for the first two hits on the enemy, regardless, I'd PD because the +3 AC and Dodge makes me the tankiest character on the field with eventual Evasion with Advantage to avoid any Dex-based AoE damage and really hard to hit with weapon attacks. Deflect Missiles mean that even if a ranged attack does manage to hit me, I can reduce or even reflect the damage.
If I need to escape melee and the enemy isn't stunned, I'd still use PD because they not only have disadvantage on me on reaction, any further attacks (like ranged) would be avoided and Evasion with Advantage protects me from dex-based AoE's like Lightning Bolt.
