You are giving these backs elite traits...
The only back in that trio that has anything that could be considered elite is Etienne and his speed...and that MIGHT be reason enough to take a flyer on him late in the 1st.
There's nothing elite (speed, power, or receiving) with Harris. He's a very good RB...cut and dry. If he's drafted in the 1st it will be by a team that has a luxury that he happens to fill (Pittsburgh). What you miss with him, you can get with Williams in the 2nd...or Sermon in the 5th.
There is nothing elite about Williams either. He is good at pass pro (not elite) and is is a bull. Nothing about him says elite. If it did he would be involved in the first round conversation. As it stands, that isn't the case.
Dobbins is in the same class as those guys. Had they had all come out last year, I doubt if any one of them goes before Dobbins...with the excpetion of Etienne.