Well from a needs point of view, we appear to be set at QB, TE, and WR. But there are always needs at certain positions (CB, WR, pass rusher) where you simply cannot ever get enough good players, so you typically take one when the value is there, regardless of need. Our particular defense is always starved for certain roles (DE/OLB hybrid, SS/LB hybrid, and DT/DE hybrid), so if you see any of those available, they're higher priority for us than most teams. So we may value those hybrid players higher than other teams, and draft them earlier than most predictions for those guys.
As for what position can be taken last, on offense I'd say TE and QB are flush with talent, and draftees in those positions may be flat out wasted. Our WR position might still be taken just to pair a good young WR1 with our rookie QB, especially considering the injuries Parker and Williams have seen in their careers. But, our WR corps is pretty solid.
On defense, we have a need of 1 more guy at every position, so any draftee adds value to the team. But, any OLB will become an understudy to Kyle Van Noy and direct competition for Andrew Van Ginkel, so it's not an instant upgrade. Our MLB is wide open, despite Jerome Baker and Elandon Roberts both having shown flashes. But, that position has lost some of its value in the past decade as the rules favor offenses and pass-first NFL offenses have minimized middle run stuffers. So that position is constantly outmatched athletically. If he's a solid run defender like Raekwon McMillan, he'll be constantly targeted with quick/fast RB/WR to expose him for an easy short pass repeatedly. If he's a light quick guy like Jerome Baker, he's going to be run over by pulling guards, FB's, or powerful or shifty RB's. So, it is rare to have a complete MLB and he isn't as much of a game changer as he used to be in past eras.
While Ogbah has played well, we definitely have room for another DE pass rusher. Despite Wilkins looking pretty solid, we definitely need another DT with Raekwon Davis having some ups and downs and Godchaux maybe not having the flexibility this defense prefers. Lawson is OK, but not great at DE/OLB, so we'll replace him when we find a good replacement, but until then, we'll probably keep him around.
On the back end, you simply cannot ever have enough CB's, and with X and Byron Jones both having health/durability issues ... we could very well go for another CB. With Rowe and McCain's age and up/down performance, we definitely need another S to push for a starting role as well as provide depth at the position. Need-wise, S is a bigger need than CB. All LB spots are open, though MLB is more wide-open whereas OLB/DE is far more important.
Sorry for the long reply, but it is less simple than the pure need positions. :/