A ford fiesta sized Subaru WRX 3 door hatch, lightweight, 300+ HP, and the option for a twin clutch transmission. I dont think thats too much to ask for a next gen subaru. I can care less if it has 3, 4, 5 doors. 90% of the time it will seat just me and one passenger. Just make it fast, reliable, and strong.
Make it look like this or something close to it: