There are some nice kits around but there are also some pretty dire ones. I'd do headlights, tail lights, debadge the rear, get a debadged grill and then decide if I wanted a bodykit.
Bear in mind it is only a 1.4 so do you want to spend loads of money it? It depends really on how long you are keeping it and what your long term plans are.
im a fan of the mk3 and personally think that there isnt a kit out there that can improve on the look of the gsi !!! so would advise source a gsi kit there are load out there being broke