From: Chicago, Illinois
Good openings, I think I still prefer the extra Panzer Corps in AGS, though.
In AGC, I find that the extra Panzers aren't going to help much the first 5 turns anyway; a decent Sov player will man the Dnepr line, and put good troops in the Woods in the landbridge. It generally will take Infantry to really dislodge all that, so I find the Panzers tend to stall a bit for lack of fuel until the railheads and infantry catch up.
In the south, you can get an earlier start on the Lvov pocket, and in follow-up turns, fuel isn't a problem. You can use those extra Panzers to get up to the Dnepr quickly.
But that's my two cents, I can see the benefits to AGC too