lol if im honest IMO not much mate, you dont want to throwa load of moey at it, a better exhaust, and a cold feed filter will help, the only other thing id suggest is strip it, will make more of a difference and is free! lol
id also say change the brakes and suspension before any engine mods
Prob buy something else if I wanted more speed.
My mum had a 1.2 Dynamique mk2 ph2 and the brakes were very sharp as standard stupidly powerful