I think though that you've may have conflated cause and effect. This sort of engine isn't really useful in a poker game. Do you remember the beautifully rendered ChessMaster games on the Amiga? I remember people talking about a 'waste of the graphics' to render chess pieces like that.
I don't think anyone has done a good Myst replacement, this might be good for that too. An archeology game? possibly. Remember that the 'engine' and the 'game' are two different things. Perhaps the 'safest' thing to imagine is an FPS, known audience, known play etc etc. Licensing isn't cheap, so if you're paying for it you don't want to risk that capital on a hyper realistic 'angry birds' now do you?
Some other thoughts on uses for an engine that does good visuals:
1 Mechanical puzzles - build machines to solve puzzles.
2 Life/City/Population simulators - more fun to watch.
3 Sex games - mentioned above.
4 Sports games - haven't had a decent FP kayaking game
5 Where's Waldo type
I'm sure there are others.