I feel like I've got little to say now as Ellie and Dorian are the two that come to mind for me as well.
Dorian is very noble, courageous and, whilst he's obviously been tormented and exiled as a result of sexuality, he still retains a kind of pride and focus and that's makes him a very admirable and selfless hero. There's other LGBTQ characters in the game obviously, but he stands out for me because as he undeniably he wears his sexuality and how it affects his life on his sleeve, but you ultimately come to admire him not because he's deals with his sexuality with that aforementioned pride and courage, but because he deals with everything with that pride and courage. Gay or not, a good buy, but being gay may have shaped him into an even better guy in the end and that's a very positive message.
Ellie is quite different. She's more down to earth and relatable, but no less admirable and that was achieved through imperfection. She's very rude, stubborn and foul-mouthed. Despite that, she's also the kind of character that somebody in the closet can observe and look up to. As I think @Crazycrab pointed out in the other thread, the main story on TLOU didn't focus on nor even define Ellie's sexuality at all and instead focused on the father daughter like bond forming between her and Joel and didn't go onto her sexuality until the Left Behind DLC and that's good because it let us bond with Ellie in a similar way Joel did. This made us care about her to the point that we didn't care about her sexuality much at all. We were surprised perhaps, but not bothered and willing to support her, and that's they way it should be when somebody comes to somebody close to you coming out. That's a very different, but equally positive message as Dorian.