Let me get this straight:
2 Heterosexual (Blackwall and Cassandra), 2 Homosexual (Dorian and Sera), 2 Bisexual (Josephine and Iron Bull), 2 Heterosexual Race-Gated (Cullen and Solas).
- If you are a bi male, your options are: Cassandra, Dorian, Josephine and Iron Bull. (4)
- If you are a bi female and non-human/elven, your options are: Blackwall, Sera, Josephine, Iron Bull. (4)
- If you are a bi female and human, your options are: Blackwall, Sera, Josephine, Iron Bull, and Cullen. (5)
- If you are a bi female and elven, your options are: Blackwall, Sera, Josephine, Iron Bull, Cullen and Solas. (6)
Looks like bisexual female elf players came out smelling like a rose this time around. 
OKAY, OKAY. I'm kid, I'm kid. So sorry, moving on. Breaking it down further:
- If you are a straight male, your options are: Cassandra and Josephine. (2)
- If you are a homosexual male, your options are: Dorian and Iron Bull. (2)
Two for each. Okay.
- If you are a straight female elf, your options are: Blackwall, Iron Bull, Cullen and Solas. (4)
- If you are a straight female human, your options are: Blackwall, Iron Bull, and Cullen. (3)
- If you are a straight non-elven/human female, your options are: Blackwall and Iron Bull. (2)
- If you are a homosexual female (any race), your options are: Sera and Josephine. (2)
Bottom line:
Straight men: 2
Homosexual men: 2
Bisexual men: 4
Straight women: 2 or 3-4 (if human/elven)
Homosexual women: 2
Bisexual: 4 or 5-6 (if human/elven)
I guess the bottom line is straight and bisexual women get one to two more options if human or elven, but otherwise non-human/elven women have roughly the same amount of romance options as men.