I'll agree with that, can't say I'm a fan of every character being into you, of the existing especially Gale, come on man, you're gonna cheat on Mystra?
Gale can't cheat on Mystra, because they aren't an item anymore by the time we meet him. And I have the feeling, that at one point, he is glad about it, seeing how fickle the gods are.
Personally I'd open him up for romance only after he's started thinking badly of Mystra, otherwise I'd keep him reserved with him wanting her back.
