I also look at it another way in terms of monetary value and resulting financial implications.
By taking Elliott at #4, you've instantly made him the 10th highest paid RB in the league at a position where it's been historically demonstrated time-after-time that you can get production from lesser pedigreed players on cheaper contracts. [Yes, I know, "but Elliott's elite!" Well, that's yet to be proven.]
Ramsey's contract makes him the just 46th or 48th highest paid DB in the league. We all know quality DBs (even middling ones) get paid "retail" in free agency because they are in such high demand. That effectively makes Ramsey a steal on his rookie contract.
Add to the fact, the Cowboys are going to be in a conundrum after this season with Mo and Carr being available to come off the books again in free agency. Church will likely be another year closer to getting cut (if not this training camp).