I'm not quite sure what the problem with bi/playersexual/whatever you want to call it characters is. It just means people won't have to make mods to enable romances with otherwise locked characters (I mean, look at how popular Morrigan's lesbian romance mod is). I suppose there's something to be said for romances that integrate the NPC's sexuality into the plot---such as Morrigan and the baby, or Dorian's family issues---but overall, it simplifies things to make all characters romantically available.
As for the complaint about there being no good-aligned women to romance: (1) that isn't true because Karlach exists; (2) Shadowheart probably isn't evil either, and even if she was, Viconia was an enormously popular love interest for good PC's; and (3) it's interesting how certain gamers feel so neglected when they still have way more choices than women and LGBT gamers had back in the day. As someone who was so disappointed when my only option in unmodded BG2 was Anomen, I find it difficult to feel a lot of empathy with dudes who think Shadowheart, Minthara, and Karlach aren't enough choices.
I don't think it's a problem per se, but there is something to be said for each character having their own sexuality to make them feel more like real characters rather than romance cutouts waiting for you to approach (which, ultimately, they are, but it's nice to hope for greater suspension of disbelief).
HOWEVER, I think inclusivity and breadth of choice for everyone may far outweigh one's desire of realism in characterization, so this is fine by me if handled well.
