2013 was the last of the 'good ones' I gather. Apparently Abarth was skirting the emissions rules with the sport button, but then CARB caught on and they could no longer use the Magneti Marelli sourced ECU. So tuning a 2014+ is hellish.
Mine is
lightly modified with an ATP 3 downpipe and high-flow 200-cell cat, EC V4.1 intake, Forge FMIC, GFB DV+, 4C coils and Brisk silver racing plugs, ported TB, an E+D phase 2 tune, wilwood brakes, and a full Bilstein B14 coilover set. There's also the rear seat delete and a strict weight loss plan which bring it to roughly 2100lbs.
It makes north of 200hp, which is good for mugging other cars you'd never expect - and that's always good for a laugh.
I flog the hell out of the thing and it's been flawless, and it's about as close as you can get to a sportbike and still have doors... And still be cheap enough to essentially be disposable.
Overall I'm of the opinion that if you've got $18k laying around, it's hard to go wrong with an Italian Shelby.