I hear he's gone off the rails lately. Dragonlance has a lot of novels though I've yet to get around to reading them. Ravenloft is mostly its own thing but does have the odd tie-in here and there like you mention. Spelljammer only got a sextuplet of novels as far as I know but it did get a comic and some tie-ins with other books. There's also Birthright, Dark Sun, and Mystara.

Personally, I don't care for the post-TSR novels outside a small handful of books. WotC has bungled the settings and/or left them to rot.