I’d say either MX5 Mk1 or Mk2 (but not Mk 3), Elise, Caterham/Westfield or Suzuki Cappuccino.
I wouldnt get anything fwd, or 4wd ie evo’s or scoobys. fwd is just dull and 4wd you have to be a bloody good driver and go stupid speeds to get any where near the limit of grip and therefore have fun.
Elise’s just give you an amazing buzz theres just some thing special about them, however on the road you will never be able to push them, and as has been said above I wouldnt want to push one on the road because they will be snappy.
I’ve only driven a Caterham on the track but imediately thought it was easy to drive and you could have fun on the road without it snapping.
MX5 easy to drive quickly but an absolute ball I had a Mk3 and wish I had got a Mk1 or Mk2 like mates of mine, they were much more involving to drive and felt more like a sports car than a normal car. Get a 1.8 with limited slip diff though.
Best car I have drivn on the road though was a suzuki cappuccino, 3 cylinder 650cc turbo charged. Not the quickest thing 0-60 but quick enough in gear with instant acceleration, fantastic brakes, and limited amounts of grip made it the most fun car I have ever driven on the road even though it was limited to 85mph.
IMO dont go for power, balance, power delivery, sensitivity give you a much bigger grin that lots of power.