Solid state design options...

Given all else being equal. All five of your parameters are all desirable goals for amp design.

Unfortunately all else are never equal. Designing andmanufactoring an amp at a given price range are always about compromises. That's why these goals are becoming more-or-less gimmicks instead. Every amp is always compromising something.

Unless the budget is astronomical, it's pretty unlikely to find optimize for all these goals.

Take a look at the statement amps from Levinson, Dynaudio, Krell, Classe, Musical Fidelity, Pass and etc should give you an idea. Even these guys don't have class A output if the rated output surpass 50-100 watts range.

The biggest class A rated output is probably Jadis 200 or the Pass Aleph series. Somewhere around 120W/ch, but they both have other issues as well.

All the discussion points to one thing. Trade-offs for the typical audiophile amps. They were all optimized for a few particular things but not everything and they can't be due to cost consideration.

It's possible to design and build a 1000W/ch amp class A, balanced, zero-global feedback, balanced and high current delivery, but it will probably cost a quarter of a million dollars per channel and the size of a sofa.

So all these compromises designer made will basically force the marketing to emphasize specific strength which usually make all these terms unimportant and impossible to compare one on one.

If you are amp buyer, don't take these terms too seriously. If you are an amp designer, that's a complete different story.

BTW, if you can't tell yet, I am by training an eletrical engineer.