Betty isn't along for many scenes, so, in terms of content you don't lose much, but, that also means, that even if you don't enjoy large girls, there isn't much that you have to endure while keeping her. I find her refreshing, but there are some around here that really are into her, they can probably say more about her.
Ultimately, this is a single player game, you follow the options you want, no one else's. So, do what either: Makes you happy or what doesn't make you unhappy (they are NOT the same thing). As far as consequences go, I don't see any, as of yet, Betty is a really remote character, and it has been confirmed that she will not be in the Harem that will move in together.
Dovahkin, follow your heart.
Peace