As a homosexual person, I don't find the need to add more same-sex supports. I mean, of course it would be better. I'd do anything to be able to marry Flannel or Silas as a M!Kamui, but the thing is I'm just grateful that I am getting at least a choice to be gay. People need to be patient and realize that Nintendo is willing to do it now, and let's just wait and see their direction in the future. Baby steps people! And remember, love wins (I just got to put it in there).
And Zero and not!Tharja are not much of terrible choices as well. I think people are just thinking too much when they are complaining the fact that both of the gay options are people that can be seen as psychotic. I mean, they probably aren't your type, but that's just life. Not everyone is going to be able to return the favour of your undying and eternal love and affections. I'd say just be patient and hope for the best for FE15.