"Starting to think about what the next model release will be, never an easy decision!"
There have been thirteen comments as of this message - an interesting comparison to the 73 in the Famo thread alone

Anyhow, my suggestions are:
The Ultimate T34 chassis - with options for the tank in either /76 or /85 configuration, the SU85/100/122 series, even the recovery option ?
M3 Medium Tank, with choices for the Lee or Grant. There's also the recovery option. You've already rediscovered the dies for the tracks - just need to get the turrets cast. It could even be riveted construction

Wierdos like me could also take the M3 bogies and add them to a Sherman hull, to make an Alamein version

Adrian.