We are now firmly in place on our new server - thus, the fast pageloads I've been getting for over a day now. Happy days are here again.
Everything I know of works as before -but faster and presumably more stable- so far, except the AC Wiki.
wilkesreid tells me he's tackling the email notifications first, then something to do with sustaining httpS addressing that enhances user security, then the Wiki.
-Later -but soon- I'm hoping for an SMF forum software update -which will make a big mess temporarily and take a few days- and any other feasible security measure we can take.