Actually what i had the main problem with is the reduction of armor max build units from 5 to 4 (including the stug)
While i normally would say this reduction is fine & correct.. the allied Player \ players can use a nasty strategy to inflict maximum damage to armor units in early game.
When attacking you can't sacrifire 88mm or anti tank units so you always take the stug to die first and then the armor units.
Having not some units to sacrifire & a reduced max tank build can be really hard for the long run.
Having a stug in 1939 setup gives you at least 1-2 units for the french campaign that you can use against such strategy.
For the 1941 Scenario:
I can only say i played 2 matches yet.
I think it may be a little harder than 1939 scenario for the axis.
So i would suggest:
1939: + 1 Stug
1941: -2 Tank, +1 Stug, +1 SS gren
[updated]Tell me what you think