I haven't really tried it yet. It's time trials but there are loads of videos out there. Plus I think you can race against ghosts from the leaderboards. Just follow someone from one of the top spots. That's my plan anyway.
Alice was actually pretty good. Somewhat repetitive and I didn't like how some achievements are for playing through the original. Mirror's Edge is awesome. I still have the hard stuff to do lol. Portal 2 is the best of the bunch though. I like puzzles and the multiplayer is funny imo. GlaDos is hilarious.
Hate to tell you but it'll probably be Ceris'. I've almost completed most of them. I only have AC2 and most of BioShock done for yours. I've been wanting to play Deus Ex for awhile so this is just motivation.