£35k... Modern, Fast & Fun

I'm on the hunt for a new car with a budget of £35k. My current commute is around 450 miles per week and my 420D has proved a great tool for the job. However, I am moving closer to work and my commute reduces so much that I will cycle to and from work.

My criteria
- Up to £35k, ideally £30k
- 4 Seats
- Coupe or convertible
- 350BHP min
- Some modern tech would be great; LED lights, HUD, heated seats
- Not concerned about fuel economy but would like something reliable

Current Shortlist

M4 CP: Can get into a 2017 facelift for £28k, quick and I like the shape but would it feel special? Same tech as my 420D. Lots have been modified and remapped.

C63 4.0 V8: Upper end of budget but probably my favourite so far. Lots of character, quick, loud and great spec (LED, HUD, Sunroof, Burmester) Though will it be costly to run? Tyres and brakes, AMG tax?

Cayman/Boxster 981 S: Had previous gen Boxster S and Cayman S, loved them but ideally need 4 seats.

911: My budget gets me into a 2015 which are prone to bore score and look dated inside

Maserati GT: Look amazing, sound fantastic but showing their age inside. No specialist nearby. Hard to move on after 12 months?

Audi R8: Would a sub £40k R8 be a world of pain?

BMW i8: Love these and spotted a few still under warranty (batteries) My concern, once the electic power has depleted will it be quick enough?

Can any past or present owners share their thoughts on the above and is there anything I am missing?

Thanks

Thanks all, going to arrange drives on an RCF, M2 and C63. I’ve watched enough videos on the M4 to know I’ll like it but I do fancy something different.

I thought the i8 had small rear seats? Added in 981’s to give a feel for what type of car I enjoy and R8 as it popped up but thought the better of it. It’s just me at the mo, so can choose 2 seats if needed but would be nice to take nephews for a spin in the Yorkshire Moors.