All entirely true. I dont think there's a way to do this that makes everyone happy. Personally, I usually prefer these things to not become the sole reason the character gets any attention and when they make a huge deal out of it and it becomes the only plot point the character has, I become extremely bored and end up seeing the whole thing as a cheap gimmick. But certainly there are people who would see a "under the wave" approach as trying to sweep it under the rug.
And I do want a love interest brought into these situations (that balances out the "swept under the rug" problem), because if you're not showing it, there's no point. But there's a lot of Kaldur's character beyond his orientation; fun, cool, quality traits and concepts and ideas that, if they were always subsumed by a "Kaldur's gay! Look! We get it!" narrative, would (in my mind) make him far less than he is. I have little interest in seeing everything about Superman pushed out of sight so DC can explore his relationship with Lois, and I'd likewise hate to see everything about Kaldur dropped and the whole purpose of his character becoming a statement on his sexuality.
Handle it the way people handled Kate Kane, and you should be fine. There was far more to Kate than her sexuality but writers didn't shy away from it either. All I want is a well balanced character; not a socio-political statement that doesn't have any teeth to it.