i would do the pod filter first since its the cheapest, and u can get one of those drift ones and they make a cool whistling sound....and get an oil pressure gauge, boost gauge, water temp AND FOR THE LOVE OF GOD will people please upgrade your brakes... ffs anyone would thing those weeny little brakes will actually stop you.
Change, all oils, brake and clutch fluid, belts, and if your timing belt hasnt been replaced then hell might aswell chuck that one in, check your water pump while you are at it, change fuel filters, intank and inline, thats all i can think of right now.