I'm not against radical changes, I am just thinking in terms of which change would result (in my estimation) in a game I enjoy playing more.
The reason I ask about pen is I'd be curious how lethal some of the fast-firing low-damage vehicles would become to armored heavies. In the case of a vehicle that has a burst of 5+ shots, even if only 1-2 penetrate, it's significant damage against something like an Elefant or ISU-152 (or even KT or IS-2, since they're so slow to move).
According to coh2db/com/stats, elefant has 110 rear armor. The centaur would land 1/3rd of its shots if it got behind it.
I know, I know, "if you got flanked you're already dead and...." but just playing it out in my head.
I mean if a centaur gets in behind an elefant it doesn't really matter what the balance says the wehr player is going to lose.
But worst case just don't crank up the pen of the units that are fast firing by as much