The other reality is the fact that both Jensen and Urschel will be unrestricted Free Agents next year, barring Urschel not getting his accredited year this year (only if he's pushed back to the PS, which for many reasons, I don't see happening at all). The Ravens are going to need to draft to prepare for this reality. I doubt they are able to or want to keep both (depends upon who wins the job, if one does, and how they perform)
I think Mangold's situation is related to questions about his physical condition. If the Ravens offered him a deal that included an injury waiver, he may have balked at it. I think the Ravens would be remiss for not asking for that contingency, as he is aging and has suffered decline in his game over the past two seasons.
I don't think Mangold is going to be our option, right now.
I think the Ravens will let Jensen and Urschel battle this out for the starting job. If they are concerned that neither fit the bill during camp, then I think you see them pursue a veteran and those two remain as depth for C/G going forward.
I personally don't see the benefit of pursuing a higher round draft pick for the C position this year. I can see the sense in grabbing one in the 5-7 round to develop this year. I think we have glaring needs in the secondary, and we need a solid pass rusher. We need another solid receiver, and some additional depth at OLB. We will need to draft a RT as well, if the plan is to leave A. Lewis inside. I would take a RT in the 3rd or 4th round if that is so.