I've had both mk2 phases, and driven a friend's wedge CRX too !
Ph2 has a nicer interior... thats it on plus point for me. Xenons are nice, but decent bulbs on a Ph1 is no problem (and cheaper to replace when they go pop!). That's where it ends in my opinion. Engines are basically the same. Brakes, size of car etc.... all the same. Some Ph2's have TC and ESP which in a RenaultSport is ridiculous and not needed. It's a Clio, not a Koniegseggegegabbavikingbus. 172 Cup has no ABS and can be tricky to insure depending on personal circumstances and insurer preference.
Ph1 has cable throttle and different gear ratios (Ph2 is slightly heavier) so its better on fuel, nicer to drive (if you're a 'driver', not a person with a driving licence), and looks much meaner, again IMO. They're older, so to the general public must be sh*t, so therefore they're cheaper to buy than the Ph2 now !
Go drive both, and see what YOU think.