1) Power - Can I power the IPac board and the attached LEDS (there should be 16-20 LED buttons on my control panel) via the 5v output of the Pi?
Short answer:
No way.Longer answer: 16-20 buttons * 3 LED channels (R, G, and B) per button * 20 mA per channel = 960mA-1.2A for
just the LEDs.
Consider either 1) using an additional power supply to power the LEDs
or 2) upgrading to a PC like you mentioned, giving you more than enough electrical power for the bling and
far more computing power to run newer/better emulation.
Either way, you can use a switchable/fused
IEC power inlet to supply power to an AC power strip inside your cab.
Scott