Edit: Someone said marauders should be used as the template for class balance, I'd agree with this. They have 3 viable specs, require good use of abilities to do well and offer a good utility ability. They're fun to play and other classes should be the same.
I said it (I'm the thread starter). Marauders would be a very good class to balance around.
And I didn't mention PT Pyros because they would be a very poor class to use as a blueprint. When played well they CAN have a lot of utility (taunt, AE CC, Grapple) but as a general rule they are pretty clunky and really only do well because of their incredible burst DPS ability. And when I say clunky I mean that they are not very mobile, and don't have a lot of tools to use. Basically without their massive burst DPS they would be another vanilla DPS class with poor mobility. You might be able to make the AP mobility argument, but they have to sacrifice a lot of burst capability for that.