I'm hoping for metal wheels with bearings. The 'metal' drive and idler wheels are already out there, and I think HL has a set of metal tracks.
It's cool to know the WSN metal tracks fit!
I really like my HL T-34. I don't plan a ton of mods but I'll eventually have steel HL gears, 400 motors and a Clark in there. It's a really sharp looking model.
Tiger I - Panzer III - Panzer IV - Chi Nu Kai - Panther G - KV-1b 756(r)
M4A3(76) Sherman - T-34/85 - M3 Grant