I'd of kept the MX-5 on the list, particularly first gen. As much as I love my VT as a daily driver and I know it will go forever and VTs on will remain common sights for many more years. I think an original MX-5 would suit better as a fun club car with better longer term prospects. Just an opinion and ultimately you need to pick what's right for you.
Within the specs you prescribed I'd also consider looking for KE/KF Laser TX3 Turbo 4WD, any late 80s Supra twin turbo with digital dash, pre 86 Cordia/Starion turbo, first gen MX-6 Turbo 4WS, or dare I say instead of a V8 Commodore I'd go after a ZK/ZL Fairlane, could have a lot of fun with one of those beasts!
Good luck with the quest, I can't wait to score a hobby car/classic, about 10 years away for me, once the kids are gone.