wiring harness questions?

[cycleguy55]

I have a West Coast Cobra that was wired, then re-wired - much of it without regard to colour coding, marking or tagging. Some of the wiring has been 'abandoned', and it's a mess under the dash. I could post pictures, but that might just sicken some purists. LOL

Adding to that is I'm also replacing the '80s era Ford steering column with one from Speedway which, of course, necessitates moving ignition, wiper and high beam switches to the dash. The Speedway column has a GM connector for wiring, so I have to adapt the Ford wiring to GM. I'm contemplating tearing it all out and re-wiring it with a kit / harness.

Questions:

1. How many circuits do I really need? I have a Summit / MSD ignition box, wipers, electric fans and fuel pump, and the WCC blower motor. No A/C, no stereo (ripped it out). No EFI today, but may be adding that at some point.
2. Is there any benefit to using more circuits and keeping some systems separate from others that would otherwise be combined with fewer circuits?
3. How much work is it to basically start over and re-do the whole mess?
4. Would you do this if it was your car?

TIA