With the Sherman, they could give us variants very quickly, and the variants were numerous. Also, in Tank vs Tank scenarios, you could balance it out to 60-40, more Shermans, to keep it historically correct.
Adding the Sherman may get some brain waves moving too, like, how about the ability to leave little mines around an vehicle field that will stay 'active' for ,say, 30 min? No more Mr.Goon coming in for a sweet landing without Picture #2 being present. Or Rockets into an airfield from a Sherman? (See picture #1) Having trouble with Mr.Panzer taking your SHerman out with one shot? Drive the Bulldozer version, now it takes 4 or 5 shots (unless he moves to get to your side armour)or using the blade to level structures such as AAA

...the combinations are endless...
I'd vote for the Sherman, then the T34, then re-visit German armour, with the Panther or TIger.
[This message has been edited by Ripsnort (edited 07-31-2000).]