Sounds like a good start. You're most likely not going to see jack diddly from the intake, my dry humor gets lost on forums. Removing the cat on the other hand would make it a bit more free-breathing. Guessing since that's exempt you were going to just toss a straight pipe on it.
If you stuck to mid grade or above fuel I think you could advance the distributor enough to see some gains and still be safe.
Since you'll have the tranny off already, had you considered a lightweight flywheel?
Some more info on what flywheel and clutch combos are interchangeable between the VG30E(T), KA24DE, and RB20/25DE(T). Be careful here. the VG30
DE(TT) looks like it's got a different bolt pattern\count (8 over our 6) and wouldn't work.
You can source the RB20 flywheels for
less than $150 on eBay all day long. They call it a white bunny setup for the KA engines. I'm running one myself. I've never heard of anyone putting it on a VG30E though. Seems plausable. I can grab pictures and take some measurements if you're interested.
Stock ignition system seems pretty stout to 300/400 whp (just an aside.) Might do to toss a new rotor in there and clean off the points on the cap though with some good ol' 80 grit.
As for the electric fan, I have a used OEM electrical fan out of an S14 240sx if you want it. You probably need something that's going to pull more air like out of an old Taurus or something similar though.