I really enjoyed both expansions. It definitely feels like the best playthroughs are with the Jedi Knight and Sith Warrior though, as they have the strongest connections to Valkorion/Vitiate. Apparently BioWare were originally going to give the non-force sensitive classes force sensitivity, which would've been really interesting but I understand why they didn't go with it.
The whole alliance thing was pretty good, but I am glad that we're going back to Republic vs Empire.