1: Adept, I am all for reflavoring Monk class to be something else than martial artist closed in a temple. I only played one monk in 5E and it was completely removed from the stereotype. I played Monk as a High elven guardian of Evereska. As elves are very agile, I felt it was kind of stupid to play fighter and having heavy armor training in the first place and I wanted a warrior that is always ready to face danger without any preparations. Monk class was perfect for my idea.
But the name of the class could get some more work. Adept? It was an NPC spellcastin class before, and it means just someone who has attained knowledge, or earlier in latin, knowledge of transmuting metals. Not much room for martial arts.
Also as you describe a pit fighter, or a modern version would be a MMA fighter, there is nothing mystical about it. No ki or chi or some other name for "internal energy" of "life force", no reason for slow fall or water walk or similar stuff. Also you have picture of a guy in pretty substantial armor. Breastplate I would guess? So that is going from no armor at all to medium armor.
A pit fighter is nothing more than A FIGHTER, most probably a battlemaster for some grappling/tripping maneuvers with Tavern brawler feat and/or unarmed fighting style.
But then again, I don't know how your take on Adept/Monk/Martial artist will look in the end. Maybe you will get rid of most of the ki/chi powers and have the class more grounded in that way...
Or maybe just axe the whole idea of an martial artist class. As you do not bring a knife to a gun fight, do not bring your fists to a sword fight.
remove the class, remove unarmed fighting style, and rework tavern brawler feat as:
Martial artist: requires 14+ str or dex
- your unarmed strikes deal 1d6 damage or 1d10 damage if you have both hands free, not grappling and not being in difficult terrain or climbing or swimming(without speed for those movements).
- you can use STR or DEX for your unarmed attacks
- when you are grappling someone, you have advantage to unarmed attack rolls and deal automatic 1d6 damage to anyone you are grappling at the start of your turn
- as a bonus action you can make one unarmed attack, one grappling(need one hand free) or shove attack.
- you are proficient with improvised weapons.
2: Herald,
yeah, names for this class all have some historical/religious baggage or are just lame. Maybe just cut your losses and stay with Paladin.
They are fictional knights in the 8th century, so... who cares. Yes, they were defending christian faith, but just describe them as militant branch of the faith(any faith).
Templar is nice name, but again we go into 11th century, this time REAL order of christian knight, so that is a bigger issue than paladin.
Zealot(but also a subclass) could be fine, "paladins" could all be played as religious fanatics(most of the time, they are).
We had real Zealots but some political movement in the 1st century could be far enough in history so we could ignore those implications.
Champion is taken as a subclass, but is one of the best candidates, Defender is to niche,
Now for Herald: either an office or arms or more narrowly it can be royal messenger. Pretty lame for such strong class
any class can be a herald, it's mostly profession, an official duty.
3: Beserker:
Now, I love the barbarian archetype, but it IS narrow.
You can justify the range abilities and animalistic traits as someone that HAS to remain mostly uncivilized and being in wilderness. As wild nature itself fuel the primal instinct of a barbarian. Barbarian can come to town and be there for a while, but never feel at home there. As I said very narrow RP range, but I like that idea.
maybe barbarian can be a subclass of beserker. Animal totem barbarian seems like a prime candidate to keep the candle burning.
Beserker is a good name, juggernaut could be a close second, but that is used in Battle defense, so unless you change your mind...
ah...end rant...
