Power Level:
Adventurer
With no power comes no responsibilities. To me, "metachampion" implies that people will be expecting me to help them instead of just following my own whimsies.
Plus I enjoy playing on hard mode in CYOAs.
Powers:
Immortality
Freedom
Free shit, and they don't give me points for abandoning them. The effects are solely beneficial. There is no reason to give these up.
Reality Shifting Lv1
Expensive, but being able to merge my favourite worlds together sounds too fun to pass up. Plus it gives me the ability to ask questions like "What if the Pokemon universe was designed by a competent designer?" and merge shit together to see species I would never have been able to come up with on my own.
Pocket Dimension Lv2
My own little universe that I can do whatever I want with. I technically have no reason to ever leave, but it might be fun to go out and explore the "real" worlds once in a while, even if it's only to pique my imagination and come up with new coats of paint for my own worlds.
Nullification Lv0
Invulnerability Lv0
Safety net for myself.
Mind Lv0
Intelligence and willpower are great to have, and this is a mind capable of handling immortality which makes it a no-brainer option.
So yeah. The plan here is to just jump between universes and play around however I want. Would have been nice to have psi powers or peak physical fitness, but those are just nice-to-haves and not absolutely necessary.