Issues:
Monk DPR falls off in T3/4. As they reach "I can flurry every round", their DPR stops growing with more Ki.

Your T3/4 boosts are... a reroll on one attack on their turn (14), going invisible in combat every combat (18), and capstone (which is a bit late).

Stunning Strike:
You wording doesn't match the spoiler comments. Did you intend this be once per round? Your wording doesn't do that.

It makes it once per attack during your attack action, I think. Except bonus actions are a kind of action, so arguably it just blocks it from reactions? Or maybe not. It is unclear.


Also, note that Gloom 3/Fighter 2/Monk 6 becomes a better stunner than the Monk 11; it can alpha-strike 6 stuns on round 1.

Perfect Self
This becomes a bit non-linear in effect, sort of like damage reduction. Subclasses that spend 1 ki repeatedly get huge boosts to endurance, a similar subclass that spends it in bigger chunks gets less of a boost.

If this was in the base class, subclasses and the like would factor it in. But you'd have to audit every subclass.

Ki Sense
"until the end of your turn." sad face; between turns you have no ability to see them.

It is a "ping". Are you daredevil or something?

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Things to consider.

1) Make stunning strike 1/action or bonus action. This removes boost from 3rd attack in an action, and makes the monk attack (2 tries to land) and bonus (2 tries to land) interesting.

Also maybe make it trigger "for free" on a natural 20 (not a crit, as that makes expanded crit range a bit too synergystic) not counting towards that. A little bit of serindipity is fun.

2) Some kind of targetted DPR boost at 11 and 17. My variant gave the monk a free Ki to spend on anything except healing on every one of their turns.

In theory subclass features fill in that gap, but classes without subclasses at 11/17 tend to get huge raw power boosts, and subclass features tend not to measure up.

3) To fix Step of the Wind, I waited until 11, where I let the monk take 2 different bonus action Ki abilities.

4) One change I did was to make Str be a somewhat useful 3rd tier attribute by letting you add it to damage when you are unarmored (via MA). Your AC is Dex+Wis, and your damage is Dex+Str.

The main goal was to make the 8 strength monk less of a thing; modest investment in strength makes you hit harder. Dex is still stricktly better, as it adds to attacks, damage and AC.

5) My version of Perfect Self was 2 free Ki on your turn (to spend on anything, including healing now, upgrading the level 11 feature)

6) At 17, I added the ability to burn Ki to reroll attacks you make or attacks against you. Limited only by spending Ki. It fits the approaching perfection thing.

That is your level 14 feature here, but on steriods. Also, the ability to reroll to fish for 20s to stun is amusing if expensive. The free Ki from the level 11 feature, together with your large Ki pool, makes something that burns Ki like crazy fun to use.