If you don't have any trouble, you really shouldn't bother with them. IMHO they're just tiresome, boring hack 'n slash levels. I finished the whole game without visiting the BF (well, without fighting there, I did buy stuff from the merchants there) and I did just fine.
The fifth quest by the way you can get from Keith (he's always hiding someplace). I believe in act I there is a path leading north of the village, he's at the end of the path.
