Must haves:
Night Vision: a must for melee chars and early game town raiding at night. Helps in labs, too: smg-roombas secubots can’t see you in dark.
Scout: OP, even more so with binoculars.
Fleet-footed or Quick: again, must for melee chars. Later a bit less useful, but extra movement points save your bacon when fighting sleepy, hungry, thirsty or in pain.
Cool stuff, not obligatory:
Robust genetics: for chars chugging mutagen. Bionics are usually more powerful, so I get this less frequently.
Fast Learner: less grind! I haven’t got all day to up my mechanics, for instance.
Fast Reader: ditto, but less useful IMO.
Stylish: again, less grind. Jewelry really helps. Much more powerful than Optimist or Psychopath after a bit of looting. Provides Groom, butler and Ballroom dancer with a bit of earlygame morale, too.
Packmule: useful, but costs a lot.
MA (Krav Maga): costly, but the coolest unarmed style in long term.
Poison resistant: clearing anthills and beehives for loot, surviving bloated zombies w/o a gas mask.
Disease resistant: very useful, but only for challenging builds.
Decent tradeoffs:
Addictive personality and Lightweight: drugs are semi-rare and you’ll really use them only earlygame as a panic button, later they’re more of a hassle to manage.
Asthmatic: can royally fuck you up if you can’t find a hospital or a pharmacy early and at least a couple later in the game. Otherwise, pretty harmless.
Glass jaw: still very powerful. Just wear a helmet and don’t mess with npcs or play chicken with turrets/secubots.
Lactose intolerance: few recipes actually use dairy, so it’s a free point.
Heavy sleeper: usually ok.
Insomniac: a bottle of cough syrup deals with it.
Poor hearing: even poor hearing isn’t poor at all.
Truth teller/ugly I don’t use at all because of cheatiness.
Everything else is worse than stat upgrades (Str>Int>Dex>Per for melee or Int>Per>Dex>Str for ranged). I don’t take any skills at all, leaving only profession freebies.