Hey, so what about that T-26?
One of most popular tanks in late thirties. Was used thorough WW2 by Soviets, (Nationalist) China, Finland and Germany - to name a few! Also one of most widely used tanks, it was present on fronts separated by thousands of kilometers (like Finland, Persia and Manchuria).
Kit could be composed of :
main body, bottom
main body, top (with flat surfaces to attach armor options according to variant)
eventually : main body, under-turret box (depends on implemenation)
tracks&wheels
cylindrical riveted turret for early models
conical turret for late models
two separate engine covers (old and new wariant), to gule on 'main body' over the engine compartment. Note : only cover, not the whole engine deck
two variants of frontal plate - multiple rivets (old) and flat (newer), to glue on 'main body' on the front
two variants of glacial plate - old and new style (different hatches) to glue on 'main body' on the front top
three variants of side for under-turret box (riveted, non-riveted, non-riveted and sloped) to glue on 'main body' sides
two variants of turret ring - old and new, to glue on 'main body' on the top
add-ons - road light, big and small fuel tanks, two variants of silencer, extra MG to mount on turret, tool box, rope
for extra star :
extra two riveted turrets for twin-turret model
exchangable guns for turrets (MG, gun, flamer)
horseshoe and hand-rail antennas for command tanks
Kit composited in such way would be extremely adaptable - you could use it to make almost every variant of T-26 since 1931 up to 1940. Also, such composition guarantees that kit could not be used to create multiple instances of one vehicle from one kit - at best you have some spare turrets and few extra plates, which still require something to glue to/at (armor plates are glued onto main body).