weight reduction and a good service, maybe invest in some decent tyres and some springs to try make up the lack of umph with better handling in the twistys.
Not a lot you can do tbh, dont bother with induction kits and zausts as on a 1.2 all you will gain is ear ache
Save it for a Clio 172/182 imo
put some redex or additives through and maybe put some v power in