The controller PCB has been reworked several times since the last post, but thinking I'm finally starting to settle on things. Switched to JEDEC MO-299 (HSOF/PSOF) package instead of TO-263 since it is a bit smaller overall and same price (80V, 3mOhm, $2.50~2.60 each at 10+). The VIN+, PHASE, and VIN- connections are separated 20mm on center vertically and each half-bridge is separated 24mm on center horizontally on a 100mm x 100mm board (with M3 mounting holes on a 94mm square) with the PHASE connections centered at 50mm vertically. The top 20mm is taken up by the resonant snubbers and the bottom 20mm is currently blank with all signals routed to a 2x24 header (2mm header pitch; two headers spaced 18mm apart).
The power connections are 5mm plated vias under the MOSFETs (for VIN+ and PHASE) and in free board space (for VIN-). They get a Cu-110 plug press-fit into them. The plugs are 6.35mm rod cut 6.35mm long with the press-fit side having 12 divots spaced 30 degrees apart milled out by a 1/8" endmill at a radial distance of 3.925mm to a depth of 1.5~1.6mm. The other end of the plugs are milled to a square 5.675mm on a side to a depth of 2mm and a centered hole 1.6mm in diameter to a depth of 3.75mm (hand tapped to M2 or self-tapped by screw). The mating surface for the plugs is a 2mm deep cutout made from a 1/8" endmill tracing a 2.5mm square. The VIN+ and VIN- buss bars are simply 0.25"x0.5" Cu-110 bars with 2mm holes spaced 24mm on center with a 4.2mm through-hole on either end for M5 screws to attach power leads. The PHASE connectors are 0.5"x0.5" Cu-110 cut ~0.5" tall with the plug mating surface milled into one end and a 2mm through-hole centered in it. The opposite side gets the 2mm hole expanded to 4.2mm for a depth of ~8.3mm to accommodate the M2 screw's head and for an M5 screw to attach power leads. Should wind up with the VIN+ and VIN- buss bars hidden under polycarbonate or delrin plate with cutouts to keep the PHASE blocks nicely isolated (and provide additional resistance to blocks rotating). The M2 screws to attach the VIN+ and VIN- buss bars are 10mm long and the M2 screws to attach the PHASE blocks are 6mm long.
If the M1585 (15mm x 8mm x 3.5mm N50) magnets from supermagnetman are actually going to be restocked, then each 32mm long rotor will be made from 20 of them on a stack of six 5.5mm hardboard spacers from ponoko for a ~$20 rotor. Would be ~$30 each for an entire motor including donor stators, new windings, new shafts, and new bearings. Cost likely increases a bit if I have to make new endcaps to clear the windings instead of reusing the original castings.