I kinda wish we'd gotten a bit more character development and story on all of them before going "Oh yeah by the way this person is gay, now back to this awesome story I was telling..." I like how ME3 handled Cortez, even though he didn't get any major amounts of development, it wasn't really hammered in that he's gay when you find out about it, if you even got to that reveal anyway. But this just feels like "LESBIAN SURPRISE! -Rainbows-".
I'd have rather them focused more on building up these characters more before any reveals on romantic relationships. Either that or just have it mildly introduced when we were learning about each character in the beginning. Let the shippers and artists have their own headcanon (which they'll continue to do anyway) and keep with the world-building.
Don't just have 'em be gay for the sake of inclusivity, or just leave out the romantic relationships altogether, let people (keep) form(ing) their own stuff on them.
This also reeks of being a safe choice, with Tracer being the face of the game (she's the only character on the front cover of physical copies), despite the diverse cast of characters, and being the cute lesbian is pretty much the safest way to introduce an LGBT character. I'm not against it, but either fully commit to the deal or just don't do it.