It's absolutely fine to be more inclusive. I mean, I think we can all agree that New Vegas did it right. It had all sorts of characters, lesbians, gays, ambiguously bi, ancient mutated war machines with the minds of crazy grandmas, necrotic vaqueros... They were characters, and they all felt quite natural. Making every NPC bi just so every player character can have a romance with them is idiotic and Mary-Sues the player unnecessarily.
There should be more varied main characters. No need to play the same brown-haired white dude all over again, although for some games that's just the most fitting prototype. I'm sorry for not believing in social constructs, but I'd find a short fat lesbian rather unfitting as a badass space marine. Female badass space marine? Totally works, just look at Vasquez, I believed every minute of her. Linda Hamilton as Sarah Connor in Terminator 2, and Lena Heady later in TSCC, absolutely. But Emilia Clarke as Sarah Connor in Terminator: Genisys? Nope. Physics don't lie, and I cringe everytime some tiny skinny girl throws around dudes two heads taller than her. Technique can only do so much, and if Ronda Rousey fought Hafthor Björnsson, she'd fucking die, simple as that. Or any male MMA fighter, really. Come to think of it, she can't even beat female MMA fighters these days... But I digress.
Yeah, there should be more varied characters. Maybe less Octavia Butler style of "ugly black woman brings humanity to salvation by eradicating heterosexuality" and more like Simon Ings' "muslim warrior woman fucking kicks arse in the most grim cyberpunk world you can imagine".
Just write a good character, not because of politics, but because of originality where it makes sense. Fat lesbian xenoarcheologist on Mars? Sure. Fat lesbian Spess Merheen grunt? Maybe less so.
The thing is, the brown-haired white dude is safe. It's bland, and you don't offend anyone when you let him do horrible things, let him be a walking stereotype, or do horrible things to him. You might get scolded for using too many clichés, but that's about it. It's the disposable character, as replacable as it gets. Safe. If you write a minority character you have to avoid all sorts of traps, because you'll get a lot more shit. From all sides, really, not just the SJW crowd.