Shared (and not shared) characteristics of games OR “Is this game like Britannia?”

At the NC State Tabletop Game Club I attend five people were playing my prototype “The Rise and Fall of Assyria”.  Someone came by and asked if the game was like Britannia.  I answered no, because this game is much more fluid, is designed for 3 to 5 players, has less randomness in the combat though still using dice, has simpler scoring, and involves the rise and decline of empires rather than ones that can in some cases play through the entire game (as with the Welsh and Picts in Britannia).