These have probably been mentioned, but I haven't read through the thread, so just take them as +1 to the original poster.
Two large, heavy, powerful sedans. Say analogs for the XJR and S8(y'all can keep your M5s, I'd rather own one of those two
![](/static/smilies/razz.gif)
). One is heavier, 4WD and more powerful, that's more stable and has an advantage out of the corners and down the straight, the other is lighter, RWD and a bit less powerful being better on the brakes and mid-corner. Use some jumble of Jag/Audi/Merc/BMW/Lexus/Caddy styling cues.
A RWD companion for the UFR and XFR. If you want modern styling, go with Miata/Pontiac Solstice looks, or go classic with some kind of Lotus Cortina/Nissan 510/BMW 2002 knockoff. A non GTR version could also serve against the UF1 or XFG/XRG depending on level of tune.
Two more members of the F0X family; one slower, one faster.
Make something more along the lines of a Formula Ford or Super Vee by taking off the wings, narrowing the tires 10-15mm, reduce the body/undertray downforce by 5% and add 10% drag(graphically, remove the flaps on the sidepods- exposing the spinning rear wheels to the free airstream will hurt aero), swap in a 4-speed h-patern(give it a longer shift time) and bump the power down a little. Keep peak torque the same, but reduce peak power 10-15 by moving the tuning lower in the rev range.
On the other end, the new tire model has taken some edge off the F0X, so maybe a more powerful version is in order, too(though still noticably below the F08). Keep the chassis, but bump the engine up. Give 'er a bore over to 2.4-2.5L. Call the former the Kit and the latter a Skulk.