Something with 4 axis, decent travel (12"+), ball screws with servos and 2hp+ would do nicely.
If it would work with Mach 3, that would be nicer.

I guess I could be happy with 3 axis, 8"x8"x6", 1/2"-10 Acme with steppers and G540 driver. Aluminum, steel and cast iron construction, mounting a 3 1/2hp variable speed router.

We'll find out when it's done. 8)