Interesting. There are quite a few things to figure out and it would be easier to incorporate them in the initial build, then to add-on later. If I want to bolt the motor unit to the structure I should embed threaded inserts and have space beneath to accommodate the bolts.
This Kenwood ARCB stuff will probably be like working with clay or epoxy putty. I should be able to add on layers. I know you can drill/cut it, although a little messy. Polyester resin is auto body patch material (Bondo), and I'll have to experiment with mixing and sculpting. Seems a whole lot easier to drop it in a plinth.
I could build a better (than stock) plinth and I wonder if the pod approach is worth the extra trouble. I'd have to make arm pods as well.
Still mulling this over, but pods are intriguing. I also have an old Sota Sapphire I don't use cause it can't keep proper speed. If I podify that w/new motor, I could have 2 set-ups and 4 or 6 arms and sell a few tables. Sounds like a plan.