Coil packs/Harness aren't necessary unless there is something wrong with yours. No problem with refreshing the 20 year old stuff though.
Gauges aren't necessary on a daily but are handy so I'd probably put them in.
Converting to MAP insn't necessary but if your going to a Haltech ECU then it is worth while. You'll probably need some sort of hard pipe kit if you're getting rid of the AFM's.
Stick with the radiator you have. The standard one is fine, even with mild track work.
I'd be searching for vacuum leaks and other issues that are stopping the car from making boost before pulling the turbo's out as that's a very labour intensive job and probably isn't the issue.
For the Hicas, I'd just throw a lock out kit in. No point in swapping sub frames. Just change out the bushes needed while you're under there.