I've been thinking that 3055's were a bad choice to begin with. There's just alot of heat to deal with. I didn't realize that MOSFET's could be had so cheaply.
If I have MOSFET's all around in this circuit (attached), the middle set of transistors won't really need any current to speak of, will they? If fact, if the other four use digital-level signals on the gates, I could just use any puny old transistor in there, right?
BTW, Thanks for your time in answering my questions. People can be jerks, and you guys have been really cool.