re: the M10
Except for the mission - "Tank Destroyer" the M10 is quite different from the M18. Totally different frive train and chassis. The M10 is taller and more angular. The M10 also offers several advantages for a producer of military miniatures;
1) The M10 came into service much earlier. The earliest M10s saw some combat in North Africa and they continued in use through the war in Europe. M18 didn't get into action until Normandy. This means that an M10 can be used with several different campaign sets or to support different series of soldiers.
2) The M10 was exported under Lend-Lease while the M18 was not. An M10 can be painted for US, British, Free French and Polish units. Plus, there are often several paint schemes/camouflages for each nation. This helps keep basic production costs lower, better for you and lower prices for us.
3) Adapability - not only different color schemes, but several versions are available. The basic hull stayed the same, but the M10 underwent an evolution in turrets over its production. So you you could produce an M10 hull and offer different versions of the turret, even including the British "Achilles" re-armed with the 17-pounder AT gun. Add some method of varying some of the stowage on the hull and you end up with several different vehicles with re-tooling the whole works.
4) The open turret allows figures to be displayed, an advantage to the figure company.
A few suggested versions;
a) US M10 with mid-production (or late production) turret in winter "whitewash" scheme. This could include an extra MG on the turet (a common US modification) and a crew in winter outfits.
b) A British "Achilles" with e late turret and the 17-pounder gun in colors and camouflage of Montgomery's troops in Europe. Obviously a Britsh crew set would be needed.
c) A Free French M10 (with mid-production turret) of the 2e Division Blinde (2nd Free French Armored Division) that was part of the US breakout from Normandy. If I remember right, some of these were manned by ex-naval personnel who wore French Navy caps and shirts with uniforms supplied from the US. The blue Cross of Lorraine insignia and other French markings would add a splash of color.
Again, a basic hull, a couple of turrets, one different gun, and the different figures and you have three distinct versions of a significant combat vehicle, with options for more in the future.
It might be worth considering.
Gary