Honorable mention - Does this fit my character's RP/Background? Things like Tavern Brawler and Keen Mind aren't super powerful, but add flavor with a dash of situational usefulness.
I hope the "Tavern Brawler" implementation in BG 3 will give my LVL 4 Thief a second attack / action:
https://rpg.stackexchange.com/quest...at-better-than-a-stat-bump-to-str-or-dexIt also bumps Berserkers proficiency with improvised weapons for throwing attacks.