Honestly I still prefer the exterior look of the New Edge Mustangs. There's just something about them that I can't put my finger on.
I suspect it's because you first started to drive about the time the New Edge was the "new Mustang".
The S197 is built on a much longer chassis - 107" wheelbase vs 101" (to the nearest whole inch). That means it can be made a bit 'sleeker' (I like that better than "less boxy"). The S197's C-pillar is much better integrated with the rest of the bodywork; to me the New Edge greenhouse looks almost like an afterthought with its sharp break.
Car drives and shifts great
Getting rid of the triangulated 4-link (with or without the quad-shocks) and going to the 3-link/PHB arrangement was a huge step in the right direction as far as handling composure is concerned. It's arguably at the top of the heap as far as "simple" stick-axle suspensions are concerned.
Stock ride height is pretty high. I saw someone selling the Eibach Pro-Kit (35101.140) around town for $100, but I'm not sure if those springs would require an adjustable panhard bar. If not I'll pick them up, but I don't the funds left over a bar if it's needed.
If your '07 hasn't had its shocks and struts replaced with something better than OE (or worse, mass-market OE-replacement), you'll want to budget for those as well. Springs with increased stiffness need better damping to properly control them, else the ride gets bouncey or floaty.
Shifter is fine, but has a huge throw and lots of slop. I know everybody loves the MGWs, but I'm skeptical they (or any shifter) can make that much difference in feel aside from the throw distance. Do they really work that well?
I don't think the OE shifter is all that bad when new, but it does seem that wear and tear over time and miles introduce some sloppiness. Not all of it is in the shifter proper - there's a separate link between the shifter and the transmission's internal shift rail that develops play over time. Even the better aftermarket shifters (MGW, Barton) can't eliminate this source of sloppiness.
Keep in mind that short-throw shifting typically brings increased notchiness along with it. I fabbed a short shift lever extension to "de-notchy" the MGW I installed in my '08 a while back. I find it much easier to deal with a little more throw than a lot more notchiness. That's in normal street driving, autocross, or higher speed road course driving. A 100% straightline-oriented street/strip driver might not mind notchy and hate the longer throw.
I always like the vista blue but I'm not sure what direction to go as far as exterior mods. I always like the blacked out look, but I'm not sure how well black stripes would work on Vista Blue. Silver stripes would look great imo, but dunno how they'd look with smoked taillights/decklid etc. Any opinions in this area, or any of the above?
Black stripes would be subtle, and far less likely to become "dated" a couple of years down the road. No opinion on a smoked decklid, but IMHO smoked taillights are just as bad as 'clear tails'. If not worse because doing so dims the lights.
'08 GT coupe, 5M, wheels, tires, pads, fluid, a few suspension mods . . . still almost stock height
'19 WRX, 6M (hers)
'01 Maxima 20AE, 5M (spare, winter driver)