Well that depends on what you consider you need and what you will and won’t put-up with reality-wise.
While 1941 does indeed have new sculpts not in any other version of the game, there’s a LOT of repeats for countries that never used said-equipment…
Let me clarify… 1941 has one tank model (IS-2) FOR ALL ALLIES… one fighter model (P40) FOR ALL ALLIES… one tank (Tiger) model FOR ALL AXIS… one fighter model (FW190) FOR ALL AXIS… so on, and so on.
So you’ll end up with British IS-2 tanks and Japanese FW-190 fighters for example. I’m not sure what you’re looking to get model-wise out of 1941, but I just thought you should know, not all the countries get sculpts of units they should even have in the first place (like German battleships made in Japan).