I like the practicality, but since I never put people back there, only stuff, I would prefer it if they maintained most of the space but moved the rear wheels forward about 10". This would eliminate the possibility of +2 seats due to wheelwell intrusion, but would shorten the wheelbase for more nimble handling while also improving the weight distribution from ~54/46 to 50/50.
I really think they should keep the 86/BRZ as 2+2 models but add shorter-wheelbase 2-seaters as described above to the lineup. They could call the Toyota the 2000GT

That would be close to the perfect modern sports car for me.