Don't know if this will help, but here goes ...
A/C ... check out a post called
HVAC which I did a while back. Got some pretty good advice out of it.
Window ... check out another post called
control room window in this forum. There's some tips in there.
Electric ... at the very least, dedicate separate circuits to the control and studio rooms
Audio wiring ... get high quality cable for your audio. You will be happier later. I skimped a little here and got pretty much "medium" quality and now wish I had invested a little more. Also, mount the connection boxes on the surface of the drywall instead of countersinking them to avoid all those extra holes that would need to be caulked.
Isolation ... "Room within a room" (airspace in between stud walls) would give the best isolation. Multiple layers of drywall will also help. Also hanging drywall on Z-channels is a good idea. Sealing all cracks and holes after installing soundboard/drywall is also a good idea. This is a very broad topic ... there's a lot of options depending on what you want to do.
Plumbing ... I wrapped the supply pipes with pipe insulation and duct-taped r-11 insulation around the drain/vent pipe. I've noticed virtually no rushing water noise when in the control room.
Lighting ... I couldn't afford the expensive "cool looking" lighting ... so I just have simple light fixtures in the center of each room and supplement with lamps here and there.
Anyway, hope that helps. Sound Studio Construction is such a wide topic ... it's tough to get into all the aspects here. I know I recommend this pdf file a lot ... but I think it really helps you to understand the concepts and get thinking along the right lines ... here's the obligatory link
Auralex Acoustics 101
Good Luck!