^ Agreed.
Spock and Uhura's relationship was, in some way, important to the plot, so it was shown. We can't expect every relationship between every pair of crewmembers to get that kind of time. We don't see gay, or even straight, relationships (for the most part) because it's just not important to the plot.
We also got Kirk sleeping with Gaila, Kirk hitting on Uhura, and Sarek speaking of his love for Amanda. Homo sapiens, Vulcans, and the rest of the animal kingdom are sexual creatures, and Trek has never been afraid to remind us of that.
I don’t think we need a “gay character” or “gay plot” written into the next film, but the next time Kirk is hitting on a woman in a bar, how about showing an affectionate gay couple in the background?
I’ve never looked for it, but I’m wondering: with all the scenes on Risa, Ten Forward, Quark’s, the Promenade, etc., has there ever been an unambiguously gay couple among the extras? If not, then I’d say it’s overdue.