Ok so I guess I will go a little bit against the grain here?
Personally I thought it was bad design, actually terrible design.
I don't think there should be a "no homosexuality option", but their either should be a sexual orientation choice at character creation, or better yet they should just handle the dialog in a much better fashion.
When I am playing the game and going through dialog without putting too much though into it, and I end up feeling like my PC is gay, that is bad design.
In a game where I can choose to be a ruthless murdering thief if I want to, romance and the different moral aspects of it are extremely limited.
Part of what was annoying about it, is well first of all, I was getting hit on by more men than women, second of all - how limited the dialog was. Often times it was either flirt back or respond in a mean fashion - or respond to someone who is expressing inner pain/suffering/turmoil with either flirting/ignoring it/or once again being mean. How about a middle ground where I care but don't want to fuck you?
Overall it's not a surprise and not something that alone would make me not want to play the game, but the romances in Bioware games are generally crap anyways. I can see how having homosexual relations would alienate less people - and it is something that should be included and done well but how it is implemented hasn't made the romances themselves any less terrible.