Hi sweets,
In my experience boob size doesn't matter whatsoever - there are guys who like them huge, guys who like them average, guys who looove them teeny! There are guys who like them natural (or like to think they are anyway..
) and I've even met guys who actually like breasts that look obviously fake!! Oh and there are a LOT of guys who are not boob men at all and couldn't care less because they are all about the butt/ legs. (My favourites)
So I wouldn't worry. If you do decide to go for an op however, my advice would be to only increase by one cup size - that way you still look natural which seems to be more important to most (not all, see above; but they are a minority in my experience) guys.
Hope this helps. x
Oh and of course, if you do go for an op, do the research very thoroughly when choosing a surgeon.