Leslie tweeted about wanting to do a sequel just the other day.

I thought that was intentional. The joke was that she called out other people's cultural insensitivity even though she was obviously guilty of it herself and totally clueless about it.

In the book series the show is (very loosely) based on, Bellamy/Clarke is the main romance and they end up together, but thankfully the writers seem to have zero interest in going there on the show.

Yep. https://twitter.com/Lin_Man…
Makes sense since it features pretty much the entire ensemble and doesn't give too much away.

I believe the word you're looking for is bisexual, not gay. So far the show has only established that he was married to one woman, nothing beyond that wrt his romantic history with _either_ gender (because it hasn't been relevant to the plot!).
Well, except this: https://45.media.tumblr.com…
Ambiguous, yes, but a one…

Davina and Shea as well.

Sarah proposed to Tammy in the S1 finale immediately after trying to hook up with Len in the laundry room at Ed's shiva. I thought the writing was on the wall with that one.