Depends on your definition of "better". C6 is SIMPLER - all mechanically controlled. Without the GVOD, it's less efficient of course. E4OD is more efficient, not just because of the OD but the ability to lock the converter. So they're "different", each with their advantages/disadvantages. Doesn't make either one "better"; that depends on the importance of each of those differences is to your needs. I sure wouldn't swap trannies just for the sake of it.
When my 86 lost all power, it was the glow plug harness dead shorting to the intake manifold. I had numerous wires that got smoked. a little FYI, if your wire has leaked out all of its smoke, it no workie no more.
Finding the short was just back tracking hot melty wires. Fun times!