I think we look solid at the back, Mvoto seems to relish the role of leader in the CB,s and seems to make more mistakes at the back when feels he can relax a little as the junior partner. I would stay as we are. Thus also breaking the catch 22 situation of Tarky needing and getting vital experience at our level
I don't think we will come up against too many League 1 attacks that we can't handle.
As for the attacking option on the right, the ball to Croft can also come from the MF, Croft who will have the beating of most LB in our division, so much so most teams will double up on him and limit their own attacking options down a wing that we have been very vulnerable on up-to now!