i was in a league similar to that one last year....but w no PPcompletion. it had 6pts passing TD, PPR, and 20 yds/pt rush rec. and yes, having good QBs was a must. it actually devalued all RBs who didnt catch a lot of balls. Tiki was in FA there for a while, and so were a lot of other starting RBs, which was very weird.
i wouldnt disregard RBs early, but i would suggest only getting those that catch a lot of passes, and completely forget about those that dont but rush for a lot. and i would definately grab a stud QB early