Hi, I've lived in Lake City for 5 years. Cuba Gulch and Cataract are both off limits to bikers, and Cuba would be a pretty rough poach even on the downhill. Cuba has a big willows section that is hard to navigate through on foot.
Other routes you mentioned I can't really comment on much.
You might want to wait a few weeks, there's tons of snow up high still.
https://lh3.googleusercontent.com/-6CKjHkub0Os/SpvqY9e0olI/AAAAAAAABBM/VCKqyIfzfNU/s512/IMGP4792.JPGThe Snare road across from Cuba is bike legal