I feel that the waist takes priority - The calves second.
I'm tired of trying hard and waisting a lot of time (before even getting to play the game) altering my character's form in a way that makes them appear closer to what I feel is "fit-average" or even up to a "full bodied" look (without looking deformed or pregnant). I do have characters with odd or slender body types, but I want the option to give my character full or average thighs and not get Hulk calves in the process too.
Other muscle groups and smoothing-over options, like getting rid of the "triangle crotch space" on females when making thighs bigger, would be great but I don't see them as a priority - ie: causing major deformity in character creation and making it take far longer for a player to get through the process due to multiple attempts to create an average healthy-looking body base.
For qjunior, just imagine a bunch of hawt Orions on Risa...and you.