I've not heard of Linda Haldeman! Clearly I should check her out. :)

I'm gonna stand by what I said somewhere down below, though, I think for the purposes of my definition I'm ruling out anything second-world. Because second-world fantasy is very clearly a thing, and cheerful comforting second-world YA fantasy is definitely a thing, and there are long traditions of those things; what surprises me is that there doesn't seem to be a tradition of that kind of pleasantly self-insert adult contemporary fantasy. (But I don't really think of Cadfael as cozy mystery, either. Too much sad medieval death!)

....Sherwood Ring is totally cozy, though, that one I'll definitely grant you. :)