I fall into an odd slot here as I tend to acknowledge my character's own abilities within the context of gameplay as a representation of roughly what they're capable of. Say, my Crabbermind who folds GMs and AVs in half like origami cut-outs. They're dangerous as hell, but have a limit. They can't do things like soloing Hami, for example, and probably can't stop a full-blown invasion on their lonesome.
But that's the thing, right? There's obviously going to be gameplay and story segregations. One of my characters is a werewolf, and I tend to play her as the 'weakest' of my list, despite her build(s) in gameplay actually being relatively speaking very strong.
And that's where I tend to settle. Sometimes undersell, sometimes go entirely with what gameplay represents. Ultimately, that's my own personal barometer. I'm very much someone who comes from a tabletop environment, so I like to use mechanics as a grounding element to RP.