>>15853601
The SNES is not really in the list of systems in dire need of re-capping. That list includes the TG-16 (and its derivatives like the Duo) and the Game Gear. Newer CD-based systems, too, I suppose.
>>15854902
Essentially, yes. As long as the inputs and outputs are still on the same pins, and there's no difference in the input our output levels (voltage, current). It sounds complicated, but it's often like simply using a different brand of vanilla to make cookies or something.
>>15854917
If one has nothing better to do, re-capping old computer motherboards and game system boards is at least very effective preventative maintenance.
Image is all you have to do to get expansion audio from an Everdrive (with the appropriate OS version, of course). Just one resistor.