I agree with "Flanner's" advice Scotty ... enjoy the 200HP for what it offers ...
You can optimise your car's performance simply through disciplined servicing, slightly higher tyre pressures, using the best quality fuels, etc etc.
Performance tuning ultimately becomes a curse ... one modifications leads to another and then those modifications have longevity, reliability and performance consequences ... more power requires better brakes, suspension, cooling, structural bracing, and of course much bigger costs.
And ultimately modified versions fall in value - they don't rise. Collectors want factory original. And we do all own a modern day classic ... right
This isn't a critique of those who seek better performance, but a reflection on the implications ... Peugeot invested millions to develop the RCZ ... there's not much more we mere mortals can do to improve on an already enjoyable and unique coupe like the 200 THP RCZ .... other than buy an R