The whole rear engined thing in hatchbacks has probably had it's day at renault now. The Turbo I and II were made to allow Renault to compete in rallying, they made enough road going versions to qualify (the same way road going versions of the T16 and 6R4 were made in the number specified by the rules so the manufacturers could compete in these events)
The clio V6 was more a marketing excercise and Renaults stab at an aspirational market where there was little competition, Renault certainly were not making any money on these cars (te vee was possibly partly a homage to the legend that was the rear engined 5) It made people take notice of Renault, they like to think of themselves as a sexy company (they had been trying for years with their nicole / papa adverts and now their shake your arse ones) putting a v6 engine in the back of their little clio was big 'look at me' bit of publicity.
I think renault have been there now and are on to other stuff, and lets be honest here, they have little chance of re-capturing the magic of the MK1 and MK2 vee.