I couldn't agree more and was thinking pretty much the same thing as I read the initial post. While I understand the importance of being the first "anything", but (in the case of Northstar) when it comes to the point of it being the only thing that defines the character, something is lost.
Subtlety and nuance, that's the key. Byrne handled Northstar's sexuality beautifully. It wasn't shoved in your face, but was still pretty obvious if you know it is there.
I'm not saying you can't use Northstar's sexuality in a story, just don't let it be his defining characteristic. Sometimes I feel that Marvel is one step away from renaming him "Gay Northstar" a la what they (and DC) used to do in the 60's and 70's with African American characters. Black Goliath, Black Lightning, Black Panther (I know, I know...he's not American).
Anyhoo, the pairing of Northstar and Ironclad...I'm not too sold on the premise. For one, Ironclad dating Aurora? Of course, she has dated a metal man before...