So you are looking at a Clio III?
If you are getting a Clio II I would look at a 1*2. My 172 is worse around town that my 1.4 was on fuel but it is far easier to drive, probably down to the remap. On a run there is no difference in MPG. I would say the 172 is probably not much more pricier to keep than a 1.4 ; Cambelts are expensive on both of them (maybe a little more on a 1*2 due to the potential dephaser pulley issues), but I have seen dephasers with 100k still going strong, albeit the car seeing regular oil changes.
However, despite what some say on here I reckon it would be foolish to go with a cheap 172 but with the best example you could afford. I would also get an insurance quote ; Faster does not always mean more expensive. OK I was in my late twenties but my 944 Turbo was cheaper to insure than my Clio and any of my daily drivers, yet it had the most poke (300BHP vs 180BHP of the Clio).
If the insurance is still prohibitive I would go for the 1.6 out of your choices, but to be honest a solid 1.2 16v will probably be the cheapest to run out of the 1.*s IMHO if looking at a Clio II.