T1 E2 was another of a series of interwar US prototypes, most of which were develomental dead ends. This one was manufactured by J. Cunningham to a design by the US War Dept for a tank limited to 5 tons in weight. Armed with a 37mm gun, coaxial .30cal MG and powered by a 105 hp Cunningham engine. It was pretty nifty for it's day with a top speed of 20mph. Interesting and I'm sure I will collect one but I'd love to see him turn his talents to more useful bits of kit, ie those that actually saw some active service.
British Light Tank Mk II, especially the India pattern. Saw action on the NW Frontier, the only tank to do so.
Soviet T-18. Saw action in 1929 against the Chinese. Just about the only armoured action in the Far East prior to Khalkin Gol, fascinating little battle.
Fiat 3000. Yes I know you can convert a FT-17 but hey.
I'd also love to see some Carden Lloyds. Everyone had some during the 1930s and they saw considerable service including in the Gran Chaco war.
And despite not seeing any actual service, I'd dearly love a Mark VIII Liberty.