Hmm... Everything is never too big in my eyes. ^^

For me, it depends. For inflation, I kinda like for there to be a sorta limitation before things start going a bit overboard. ^^; . I'm usually okay with a character inflating bigger than a planet, sometimes even an entire solar system, but at to keep on growing and growing more and more, until you eventually outgrow reality itself, and then continue to grow so much you even outgrow the 4th wall, and then some, that's...a bit much for me. ^^; Just a personal opinion.