1JZ’d Supra would be a sweet highway cruiser. Supras can be made to turn and all, but you’ll spend quite a bit doing that. My old one stuck pretty well on the ol’ Goodyear GS-Cs, just be prepared to sit up in the seat to be able to see the apex over the passenger door sill because of the immense body roll. Without losing some major weight, you’ll never really get it to be “tossable”
Might be tough to find a MKIII in decent shape too, after all they’re older than most Miatas.
If you want to go fast, sure the 7M-GTE has weak points (stock head gasket comes to mind) but built up it’s pretty capable…