OK, so I've spent most of my life thinking about this and I've put more thought into it than "Which is the coolest" or" Which one will make me the most powerful?" I've actually considered how it would help me exist in the real world and whether or not I can trust myself not to abuse it. The issue with putting a lot of powers in the real world (and you being the only one who wields it) is that you're going to attract a lot of attention - most of which will not be good. Flying? Teleportation? Invisibility? Telekinesis? The second anyone realizes these are legit powers and not tricks or illusions, you've got a massive target on your back. Governments will hunt you down for research/containment and you'll have to spend your life on the run or as a lab experiment.
But what if you just make yourself so powerful no one can possibly stop you? Well, then we go back to the foundational theme of "With great power comes great responsibility" - I do not want the massive amount of responsibility that comes with being the closest thing this world has to God. Sure, I could just think "screw it, I'll do whatever I want, damn the consequences" but current me, without powers, does not want to become that kind of person. And I can't trust myself to live up to my own standards of responsibility if I wielded that much power.
So, if I were to have a superpower, it would need to be something lowkey enough that no one would really suspect me of being superhuman (just really lucky or skilled) and also subdued enough that I won't feel a heavy amount of guilt if I don't immediately save the world with it. And I've come up with two possibilities: Spidey-Sense + Spidey-Reflexes (I'm treating this combo as one power and you can't stop me) or perfect health/healing factor.
Further explanation: Spidey-sense+reflexes would basically mean I'm as acrobatic and mobile as Spider-Man if he were just at peak human capability, but with the added Spider-Sense I'm much less vulnerable to accidentally hurting myself or getting attacked by others. To everyone else, I'm just a super athletic guy with incredible luck at avoiding danger - no reason to suspect me of being superhuman. It's basically the flashiest and most fun superpower I can think of that isn't too super.
The alternative of perfect health/healing factor basically means I never get sick or fall prey to bodily deterioration from aging. Healing factor means I heal much quicker than most humans do. I wouldn't be immortal, but I'd definitely live much longer than average. The problem with this is that if people see me survive something beyond credibility and my abilities are discovered while I'm in the hospital or something, which might get me unwanted attention. Or when I'm 90 and still look in my 30s. Also, even though it's definitely a relatively OP ability, it doesn't quite have the same flashiness or "super" feeling that jumping around with Spidey-sense+reflexes has. I suppose I could kinda get there through training and exercise, but that takes work, you know?
