I think it should be not about size, but about the portrayal of size. If breasts are larger, they are more often than not sagging slightly. It's the defying gravity part that gets me. It's also the idea that if you are a certain build, your breasts "must" be a certain size.
Unfortunately for a lot of women, you are either too skinny or too big no matter what you do. I hear the phrase "real women are size 14+" (Australian sizing) If that's the case my friend who is a size 10, is a short gal, has a petite build (is not over or under weight), must "not" be a "real" woman. In an attempt to make over sized women feel better about their natural curves we are starting to deny naturally petite women their femininity. Women should just worry about being healthy and not a certain body type. This, however, is a mentality I apply to real life and not to games, or any entertainment medium for that matter. I'm not offended by the representation of women in games, because I can recognise that allot of the time it's an "ideal" that is being represented. I can play DOA2, watch breasts bouncing across the screen and not start screaming"OMG women are being over-sexualised again, better call the Femsquad!"
However, if they do end up striving to represent women in games in a more natural way, I don't think every chic must then have the perfect "C-cup". Give us boobs... any boobs! Just remember, big boobs + gravity! Little boobs - complex self image issues and inferiority complexes = win.