Descent:JitD is better if you play without the adventure mode thing that was added in the (third?) expansion, in my opinion. That adds a ton of setup and teardown time, and the dungeons are smaller and less interesting as well. The vanilla game plus the first couple of expansions prior to the adventure one are the ones I like the most. But yeah, expect an hour or so for setup if you already know what you're doing, and then maybe 5-11 hours of gameplay.
I made a "Fast Tactics" variant years ago (it's on the BGG site I believe) that can cut that down to 3-5 hours of play instead of 5-11, without making it any less interesting. Basically it gets rid of a lot of the inventory-juggling and so forth relating to simple things like just going back to town, and things like turns where players are ideally placing themselves before breaching a door, etc. That stuff is going to happen anyway, so basically fast-forward through that bit, was my overall intent.
Space Alert is super fun, but also super stressful for my group. We don't like being on a timer, and sometimes we'd miss the voice cues from the CD, etc.
Shadows over Camalot was one that we enjoyed pretty well, but it felt like it was too samey every time, honestly. It was great for a number of plays, but then it gave me kind of the same sense that Left 4 Dead did: okay, here comes the same thing again, but with some suuuper minor variances thrown in.
Never heard of Sentinels of the Multiverse, sounds awesome.