I've only beaten the game once on the NCR's side, and the NCR and Legion's final missions are shorter than House or Yes Man because, in the NCR, you fight Legate, in the Legion you fight Oliver, when you side with House or Yes Man, you fight both: Oliver and Legate.
Actually you can avoid fighting all together in the "Battle of Hover Dam". At least with Oliver you can while siding with House or Yes man. Legate actually needs a 100 speech, (Finally that 100 Speech Came in handy) and you can basically walk away without killing anyone.
In my opinion, Yes Man has been my favorite so far, just because of that feeling that your stabbing everyone in there back and building your own personal army..
Give it a shot. Its pretty satisfying.