I have multiple characters, many of which are exactly what a single fursona is to most people. Most of these characters are idealizations of myself, of course, so they're either lithe (strong, and slim, but not exactly muscular, like me), or they are in fact lightly toned. I like to have my characters trim and... well, quite simply, perfect physically. A physical imperfection is not as interesting to describe and not as debilitating as a mental imperfection, which all my characters have due to their being based on various aspects of my own mind, including the imperfections within said aspect. Others, I guess, could be considered physically imperfect. I have a character made to be the exact opposite of myself in everything but intellect, so he's somewhat chubby, short, Christian... those sorts of things.
So I have a few that are not perfect physically or muscular (I actually absolutely hate buff characters, the kinds that are so ripped their shoulders stick up to the same level as the middle of their head), and I have one that was made specifically not to be perfect at all, but here's the gist of what I think about characters: if I am not representing the whole of my existence with the character (which I never do, because it makes my head hurt to think about that many aspects), then I see no reason to represent the whole of my body simply made furry. I take great liberties with the character's physical form not because I want to look the same as every other furry with a mind and a fursona, but because I wish to create something that I can't be.