A shame in dropping an very doable project, probably from worrying too much of Bethesda's potential DLC (?)... As has been said probably 90%+ of the Skyrim assets could've been reused for Solstheim, which would've allowed more focus on quests, NPCs, etc.
Yes, you could make a killing with a Solstheim mod full of Skyrim's improved draugr.
Fortunately, there is a Return to Morrowind mod project that shows promise, and while the project lead has expressed no interest in Solstheim, it's open for claims.