It's not preachy. It's not much different from Steven and Connie's burgeoning romance, which will obviously build to that point.
[spoiler]The very existence of Garnet is that of true love, so of course the romantic themes between Ruby and Sapphire would present itself. And it's not like it's constantly in your face; they merely have a few designated episodes. The other Crystal Gems have their own episodes, too.
Now, the plot is shifting more towards Peridot and her alliance with the Crystal Gems. Rebecca is probably just getting some of the backstory out of the way before the showdown with the cluster and Yellow Diamond, hence the flashback of how R & S first met. She's efficiently tying up loose ends.
It's already very,
very rare that a childrens cartoon has LGBT themes, so by all means, they deserve to have the spotlight every once in a while. Jimmy Neutron, Dexter's Lab and a few other cartoons had gay characters, however, they were heavily stereotyped and not very realistically portrayed.
SU is the first to take it seriously, and not tone it down as a joke.
I don't know why you're letting tumblr get to you. Just watch the show for what it is.[/spoiler]
i think i saw like half an episode of SU, didn't think much of it and tossed it in the "can't get into it because i'm essentially locked out of the story since i didn't watch it from the beginning" pile.
Now I really have zero reason to.
That's dumb.