Standard size bases, yes, to work with the turning templates and rules, but also to hold players makers (so multiple players can play the same tank, if they want to) and speed flags.
The up-until-now unrevealed Crown tank's model is on one of the bases, although the base itself here is still rough:
You can see the speed flag over the model's shoulder. It's mounted on the stand's rear left corner. We've already changed the design of that, though, as @Kevin has thought better of using punchboard that swaps in and out of a flag stand.
Anyway, you saw it here first.
I'd love to let people 3D print their own models — that's something that was on my original agenda that had fallen out of mind.