My non-perk gv wishlist:
Sherman M4A3 [W]
Panzer IVH (already in)
T-34/85mm
Reasoning: the Panzer IV and T-34/85 are fairly close in armor penetration (taking into account poor Soviet AP manufacture), whereas the T-34/76mm would have a slightly harder time achieving parity with the Panzer IV at longer ranges. The T-34/85's biggest benefit over the Panzer IVH would be the increased damage it's larger HE round would cause.
The reason for having the 75mm Sherman M4A3 is for several reasons: 1) The 76mm Sherman did not reach the level of production that either the Panzer IV or the T-34/85 did before the end of the war; 2) the 76mm gun would be significantly better than the T-34/85mm, and slightly better than the PIVH at long ranges (1000m+); and 3) the Sherman has the best AA capability of the three (the T-34 being without ANY pintle gun)
My gv perk wishlist:
Pershing
Panther
IS-2
The Pershing is, unfortunately, one of the only tanks the US developed that could really be considered on par with the Tiger, the Sherman Jumbo lacking the requisite gun necessary to take out the Tiger in long-range fights. IMHO, the Pershing should be perked higher than the Tiger for several reasons I will not go into here. (IIRC none saw combat)
The Panther would be a great tank to include, and due to it's superior gun, speed, and sloped armor, it should probably be perked just a little bit more than the Tiger.
The IS-2 would be the Soviet equivelant of the German Tiger. It probably shouldn't be perked more than the Tiger due to it's low ammo load (28 rounds), though it does have better armor penetration and HE damage.
I love flying in AH, but sometimes driving around in a tank is just as much fun

[edited for spelling]