I've done the first few contracts for Nazir (Dark Brotherhood) but I'm not finding them very enjoyable. There's no background which would make them a bit more interesting at least, nor is there any challenge. It's simple slaughter. I'm starting to feel bad about it in fact. The orc bard in Morthal was willing to join me in the attack on the vampire master's lair, and I had to kill him.

I checked the wiki and it says there's no penalty for not doing them and they're not needed to complete the main Brotherhood quest. But when I checked the wiki for one of the contracts it says he must be killed to complete the quest.

So can someone tell me if I have to do them? Is there a penalty for not doing them? Is there a cool reward for completing them, other than gold I mean.

Thanks.

You only have to do the first six contracts (between certain quests Astrid tells you to go talk to Nazir) .
The other six are optional. You get money for doing them, but there is no penalty for skipping the other half.

This.

They're mostly just to make extra money. Money is useful. Like buying [censored] you don't need....or even have the storage space to stash, along with the other 15000 items you already hoard.

Oblivion's side contracts set the bar really high, and Skyrim's don't live up to that.

Saddly yes. That's Skyrim's biggest flaw, and perhaps it's only serious flaw, in my opinion.

Thanks everyone.

I think I only did 3 and got to advance the quest line. Did Astrid send me back to him? I remember I only did 3 that I didn't care for, though.