Polymorph: I didn't mean polymorph. Specifically I meant the chaotic aspects of the barbarian's rage which, though not technically linked to lycanthropy, have parallels: the temporary increase to strength and durability, speed, etc. That's what I meant. It's not RAW either, but it is a thematic consideration. Is the lycanthropy being used as an affliction? Then it's a curse, evil, and shouldn't be a boon (good phrase there, btw).
Werebear: I don't count the other lycanthropy types. Ever since I can remember (2e, I think started it) there have been the evil werewolves and the happy-clappy were-goodguys-because-nature-is-awesome. My original group saw the DMs girlfriend become a were-dragon. If there was a were-puppy template I'm sure someone would love it for their gnome or familiar. Natural lycanthropes could be a race, sure, and I don't mind that. I just wouldn't mix them with the demon taint of the wolfman, that's all.
Personally, I'm just a fan of afflicted lycanthropes. I don't see goodly creatures transforming people's alignments through an affliction like werebearism to be a realistically "good" thing. Evil is corruption, so I can see that; and it works with the curse/affliction aspect of lycanthropy.
In theory, a werebear Paladin would want to afflict as many orcs, goblins, and evil humanoids and human criminals with werebearism as they can. A band of werebear clerics could seriously upset the balance of good and evil, needing TN druids to step in. Make sense?