I'm surprised nobody has really mentioned CREWS, the men inside the machines.
Crew training and morale are huge factors in a MBT and in the better MBT's are a big factor in their design. I could cite many battle and campaigns where CREWS made a big difference in the outcomes.
Without the men crewing these puppies taken into consideration no matter how the other factors handled you will have 50-80 ton chuck of metal and grease, at best a steel mobile pillbox, at worst a brewed up wreck!!
