I have yet to encounter any in-game romance arcs that really felt like romance to me. Course, I'm not a terribly romantic person to begin with....
Mostly, I just get 'attached' to a (male) character or two and the romance is all in my fevered mind.
In BG1, I was quite enamoured with Xan. He cracked me up. :D
Anyway, I'd agree, when they're there, script-wise, they're usually rushed/lacking, scripted like bad romance novels...but if you end up liking the character, you don't mind too much I guess. Games are kind of a limited format for romance, IMO.