Kind of with Nocte ad Mortem here... I believe that of all of them, Solas's chances are best (Iron Bull is probably the other male). Then we round out the ladies with Vivienne, who is (most likely) bisexual but may be race gated.
It would not surprise me if Vivienne is race gated against elves and possibly qunari, since she's all about power--and elves and qunari are not precisely in good standing. Dwarves... maybe, though surface dwarves have their own problem areas. Hard to say. She might not be race gated at all; it might be Cassandra who is race gated, due to, as others said, being nobility. Though that doesn't necessarily mean she's gated against anything but human nobility--she might still romance a mage, for instance.
If both race gated LIs are males romanceable by women and gay men... well, that will be a huge problem, and I don't think BioWare would be blind to it. At least, I hope they wouldn't be. So, yes, it's looking like Solas, and yet while I will hope for him I won't expect him. Honestly, I won't be surprised at all if it's Varric, but will be quite stunned if it's Blackwall (and I'm sorry for that, 'cause I know he's got some major fans here... he's not my type but I totally get that he is some people's ideal).