These are a generation behind the x11spm-f/tpf/tf, so your capitalizing on falling ddr4 prices and v3 xeons at the moment.
In terms of building a compact system, initially I was looking at the X470DU/X470D4U2-2T, but the board is the stuff of nightmares (according to other users).
There are, of course, the supermicro e-2200 line of MBs but good luck with udimm prices and getting your hands on some of the more desirable e-2200s.