Hello,
I've add my perspective on the things i also encountered.

- Reactions don't meant to be swapped i guess, i have a battle master as my main, he uses AOO when possible. Were you not able to use them both? Why tried to swap in first place?
- They may have resistance + made a saving throw = 1/4 damage?
- Superiority dices worked well for me , maybe bugged on NPC's .
- Dancing lights does not normally stick to anything, but you should be able to move them. https://5e.tools/spells.html#dancing%20lights_phb

He who fights with monsters might take care lest he thereby become a monster. And when you gaze long into an abyss the abyss also gazes into you.

AMD Ryzen 7700X, 64GB Ram, Rtx 3080 12GB, lg-34GK950F-B,Logitech Z906 Thx.