Chaosmancer
Legend
Warrior of Shadow
Level 3: BUFF, with caveats. Losing Pass without Trace really sucks, because monks don't have a lot of out of combat options that help the whole party, and PwT is one of the best. However, getting Darkness for only 1 di point is better, PLUS you can move it, and flat out gaining darkvision is necessary to the class. This puts the pieces in place that the Shadow monk can build on later (similar to how Mercy monk also builds on its level three abilities).
Do you think it would be too much to put Pass without Trace, Darkvision (solely for allies), and Silence back as options for them to use? It wouldn't increase their combat power one iota, but it would give them back the utility they lost.
Warrior of the Elements
Level 6: BUFF???. Again, this is better than the previous version but still not great. 2 di (a third of your pool when you get this ability) to do a 3d8 (scaling) AoE at range is kind of underwhelming when wizards are casting fireballs for a smaller share of their resources at this level. But the potential is there - what if the damage instead became 2 martial arts dice PER di spent, maybe up to a maximum of your proficiency bonus? That would get it there.
So, similiar to the Sun Soul's AOE? Actually... why not just copy that?
Make it a 1 Martial art die AOE for free, then spend ki to increase the damage by two dice per ki spent. So 1 ki = 3d, 2 ki equal = 5d. Might be a bit too strong, but I'm fine with that. Or you could copy the Ascendant Dragon's Breath Weapon ability.
Warrior of the Hand
Level 6: NERF. Both versions of this suck, but I will argue that the new version sucks harder. The old version used your action but didn't cost resources and gave you a decent heal - 3x monk level. The new version costs a bonus action AND a di point but gives you a much worse heal, though you can use it more often, as many times as your wisdom modifier per long rest (but you shouldn't because the action economy on it is TERRIBLE).
This ability is particularly bad when you look at it in the context of a Mercy monk's level 6 ability: they can do the exact same heal as often as they have ki/di points, and they can do it to whoever they want, not just themselves. And on top of the heal can also remove one condition from the target: blinded, deafened, poisoned, paralyzed, or stunned. OR they can instead choose to do that same amount of necrotic damage to their target, succeeding automatically, and inflict the poisoned condition with no save, which is an amazing debuff. Oh, and they get it as part of their flurry of blows, meaning they keep the initial unarmed strike, which Warrior of the Hand has to sacrifice to get their crappy little heal.
How did WotC look at the Mercy monk ability and then decide to give this garbage can version of it to Warrior of the Hand? It boggles the mind.
I find it especially egregious because of how expensive it ends up being.
The original feature healed a guaranteed 18 when you got it, and a max of 60. It was once per day, and it was an action, but since it was an action it wasn't used in combat. It also, as you say, cost nothing.
This version is a die + wisdom mod. Now, that means that until level 12 or so, you are looking at it being +3. So, it starts with 1d8+3 or 7.5 ON AVERAGE. It is ONLY a bonus action... but since that still costs you things like patient defense or flurry of blows, you STILL aren't likely to use it in combat unless you are desperate.
So, you are likely getting three uses, which is 3d8+9, which is more healing technically, it averages out to 22.5, but that is also an average. You could potentially heal a total of 17 or a total of 15. And, it doesn't increase. By the time the Old Open Hand was level 10, this ability was healing 30 hp. This version is still averaging 22.5, because you haven't had a chance to increase your wisdom if you are focused on your dex. Now, if you were able to get Wisdom 20 (unlikely) then this would max out at 5d12+25.... which is 57.5 on average. LESS than the original peak.
Oh, and we've forgotten something. All this healing? All this healing that is LESS than what you used to get? It now costs you between 3 and 5 ki to pull off.
This is just horrible.
Level 11: BUFF. But it's not great - it lets you use Step of the Wind without spending di points...which is how Step of the Wind should work for all monks, baseline. However, the old tranquility ability was such trash that anything is an improvement.
Eh, I think all the old Tranquility ability needed was the chance to be restablished after a fight.