Well i personnally like RC way better then Halo. Halo had a good story and was generaly a good game, but the second hald of the game sucks, with the flood and all that.
Also i found RC way more fun to play then HL2. I'm guessing with only like 7 hours of gameplay to do they were able to focus on that and refine it so it was extremly good. I just hope that they will release new campaigns for it, cause they could do so much with this game.
Also it would be cool if they would add in some vehicle support, its using the U2 engine so it sounds be to difficults to do. And add an Onslaught and Assault like mode from UT2K4 to the MP.