Carle is too good to be a #7, put him next to Nesterov so Nesterov can pinch up more and keep Witko as the #7.
Probably not a good idea to have Nesterov playing his off-side in any sort of long-term scenario. If Nesterov overtakes Carle, Carle becomes addition by way of subtraction in terms of contract.
I think Nesterov might be too good to keep in the AHL next year (not sure his waiver status), but he's also too young to keep on board as an extra D. In an ideal situation, I don't think he and Carle can be on the same roster next year. It would be a lot easier to give Nesterov the job and then go out and find a $1.5m steady vet who can be the extra LHD.
We sort of need a cheap Eric Brewer.