I'd be ok with it, but they're going to have to pick up one more legit ball carrier as well, either in draft or FA.
Early in the year, Lynch will most likely be out for 2-4 games. Late in the year, there will be at least a couple games where the passing game is eliminated by weather. Right now, this team has only 2 legit RB's. After that, Omon is the only RB on the roster and his numbers from all last year are 5 yards on 6 carries. I remember him even looking unimpressive in pre-season last year. I think you have to acquire some quality here in order to spread it around.