Now the hard part would be managing the expectations of the 21ST century audience. Some people would be uncomfortable with overt sexual activity between homosexual characters (although the Star Trek novels are pretty mild in the whole "sex scene" department).
There have been a couple of pretty overt lesbian scenes in Trek Lit to date. We see T'Prynn and Anna Sandesjo in bed together in Vanguard: Reap the Whirlwind
, and there's a sex scene of sorts with Mirror Tasha and Keiko in "A Terrible Beauty" in Mirror Universe: Shards and Shadows
. I don't think there have been any male same-sex scenes yet, though.