Too be honest tho it's sad I wasnt born for all but 7 months of the 70s.
The best backfield in my time I would have to say was 2009 with ricky, ronnie, polite, Cobb.
Building the perfect backfield for me would be tough since I dont really no the old guys but in seriousness, my opinion
Csonka
Ricky
Paige, Byers or Polite at FB
Then either Ronnie or Reggie...I wouldnt even mind Byers in this spot if you chose on of the other true FBs as the 3rd.
Csonka and Ricky are utilized best in the one or two back, QB under center set.
Paige and polite crushed DL and get you one of the first two 1 on 1 vs a LB. Paige also had soft hands.
Byers could lay the wood blocking but could also be flexed to TE in certain sets and had the great hands.
Reggie and Ronnie both were said to have probably the best hands in their drafts, even topping wr's. So they can be flexed wide if needed. I might give the slight nod to reggie here tho. Ronnie had more power and some acceleration if he didnt dance, but was never going to take the long one to the house. Was always like yes TD, then nope hed get walked down once that initial speed burst was over..
So prob csonk, ricky, byers, reggie