I've heard it said that it is more fun to drive a slow car fast than a fast car slow.
Me . . . I'm kinda partial to lighter-weight cars. I realize the Miatas, WRXs (a bit heavier thanks to the AWD), Evos (when they made them), GTIs, Honda Si, etc. will never put down the same power as the V-8 muscle cars (and honestly many of these cars now can also compete with the smaller cars on the twisty tracks which used to be where the smaller imports really did well) . . . to me I just feel more connected to the car and road with a smaller, lighter car . . . if that makes any sense. The heavier, bigger cars have gobs of power and they're fun to a point, but I feel "isolated" from the feel of the road.
Yeah, they can all be very fun. A buddy was really leaning on me hard to consider a WRX or an Evo, before I bought my wife a new Audi 10 years back. They're fun cars, for sure... but they always felt like something I should've been driving at age 18, not as a middle-aged adult. Stripped down cheap plastic interiors, and an overall lack of features, aimed at keeping MSRP around $30k.
You're also right on the isolation you feel from the road in some of the higher power cars, but the winds have been changing, there. The SRT cars, and the LS1, are very responsive, and do around 1.1 lateral G's. The SRT is stiff as any small sporty European sedan I've owned in years' past, when set up in Sport or Track modes. Snap 'em back to Default mode, and they feel like your average Lincoln town car.
My cousin just bought a new ZL1 so ill check that out as well. This car is for the wife, who will only drive it if its standard shift.
Lucky wife! That's a $60k+ car. Time to make friends with your cousin!
Mustang would be my last choice,never had an ounce of luck with fords. Im a chevy guy ,so im going to test drive the lineup of newer model camaros to see what the driving experience is in all flavors.
I have also never been a fan of Mustangs, Oak. Not because I'm not a "Chevy guy" or "Dodge guy", but because I see no value in Mustang's 50-year market aim of being, "the least expensive car you can buy with a v8 in America." I also wouldn't want to be associated with the primary demographic of young and obnoxious guys who seem to gravitate toward that car. But I can't deny how damn sexy some of the newer Mustangs look. It does make me want to check one out again, someday.
Particularly, if you're looking at stuff 5+ years old, the Mustangs don't have the performance. Not only do they fall short on horsepower and brakes, but they just flat out don't handle turns very well. A 2010 SS Camaro has independently-verified lateral acceleration around 0.9 g's (depending on test house), whereas the same-aged Mustang's best is way down around 0.77 g's. Might as well be driving a 1970's Fast Back, at that point!
So, Camaro is it. Have you spent some time on truecar or Edmonds, to map out age vs. trim level, to see where each trim level intersects that $20k point? I'd be shopping for an old low-miles 6.2L SS, or ZL1 if you are so lucky, before a newer v6 LS or LT. There are those nutty guys who buy these cars, and then keep them in the garage most of their life, on taking them out on sunny Saturdays. I don't understand those folks, I don't have the same self-control to have a nice car and not DRIVE it at every opportunity, but a patient search will turn one up.