Let's think about this as an example - did Rousseau help the team more than Etienne would have? My answer is a "yes". The run game may have been somewhat better but blocking would have restricted Etienne's effectiveness anyway. Hence, even if we had the choice, Rousseau would still have been the better choice.
Fast forward to today - in the first round, a lockdown corner, fast/YAC WR or even a stud OT would help the team this year a whole lot more than a RB would.