Assassins Creed III Multiplayer

Look like the MP in ACIII has an Abstero Story that players can unlock. Bad thing is it seems that players need to complete challenges instead of just ranking up or spending credits. On the one hand I like that there is a story for MP. On the other hand I hate how I have to complete challenges to unlock it.

I am terrible at MP. Main reasons are because I usually get placed with immature/rude players or because I just completly suck at the MP portion of the game. If it was just ranking up I wouldn't mind because even though I suck I could still get a few kills here and there and rank up slowly.

I am guessing the challenges comes down to skill and I don't devote enough time to MP to get skilled at it. If this post is sounding whiny I don't mean for it to.