Was thinking the same about the breast sizes, but then again, even if there is variety, a lot of times the girls who have the breasts you like are not the characters you like - so here I could at least just neglect the breasts as a deciding factor.
With the choices I feel there is only so much you can do as a developer, otherwise nobody is happy, because the update is only 1/10th as long of a normal update, since they have to write 10 routes. Or there are basically 2 entirely different games, depending on an early branching plot choice that matters a lot. I would guess it's just a very limiting medium.