Hi,
I currently design some boards (one of them is this here: [
reprap.org]) and one of them is a 32bit replacement-board for anet style printers. It has a stm32f103ret and socketed driver. It will mostly a drop-in replacement for the old board on anet printers and with custom mounts and enough space also for other printers with an 8-bit board. In the moment I work on the pcb-layout but I upload the schematic in pdf form, so that you guys and girl see it and see if I have overlooked something.