I'm bored so here's my analysis
I look at every skill in terms of power, stealth, or money potential The game pill is also stupidly OP so I pretend it doesn't exist.

focus - this sucks. The bonus also sucks

mimic - definitely a fun gimmick, become a well-paid celebrity/voice actor. slight stealth potential as well (guising as important people, but only via phone call). But you'd still need the contacts of the important people involved so not that great.
The bonus is interesting, you could imitate car bombs and terrorist attacks and stuff? Possible stealth potential

spy - great stealth potential. Guaranteed invisibility as long as there's no cameras around--you can do any shady shit you want in a room full of people. Bonus is okay, the same skill but stronger

creature - great stealth but too risky. only use is turning into a fly or bat or something to be unnoticed, but then you get killed by a hawk or a person. Bonus sucks too

nocturnal - very good stealth potential, and also fun because dreams are fun! A very good bonus skill! (The bonus makes the focus pill obsolete lol gg)

game - Hilariously OP, just design a card game and pick the infinite-wish-no-drawback-genie lamp. I'm just going to pretend this one doesn't exist because it's so ridiculously OP and the definition of "game" is so vague. Even if it's only video games it's still stupidly OP

jumper - No stealth, but immense power. But not really bc you still get killed by a bullet. They see you jump once, then they just send you to area 51 with the greys. The bonus sucks, what's the point of landing on your feet if you take no fall damage regardless? Are you just tryna become an olympic gymnast or something, but for superheroes? lame ass

rift - best stealth potential. Bonus...is kinda underwhelming but maybe situationally good for [redacted] the Kohinoor diamond or something

wilds - possibly best stealth. Could hide in the forest without fearing bear attacks, or even bug bites (animals too!). Presumably animals would help you hide from humans? No need for google maps (which leaves cell trail) However, it is dependent on wilderness existing, which is a huge weakness. Also very vague about what "wilderness" really is. The bonus is okay, not too useful but very fun and interesting.

First choice is obviously Game Pill, which shouldn't be here because it ruins the point of the exercise. If Game didn't exist then:

1 pill only: Nocturnal
2 pills: Creature + Wilds. full stealth by turning into a bat, and you won't get eaten. This is the most OP combination

other good/funny choices:

Creature + Spy, but only if Spy applies to animals watching you too. If it does, it cancels the weakness of Creature pill: you can turn back into a human before the hawk eats you

Jumper + Rift: You get to dab on the military by becoming a living boost-glide missile playing IRL Portal 2. But the jumping would remove any stealth and you'd be killed eventually.