I guess the real question is what type of change are you looking for? Louder, sleeker, better response, etc. There are a lot of slip on options. Baron's Nasty Boy, Bub, etc. If you search the forums you'll find as lot of threads discussing the pro's and con's of all types of ehausts.
As far as maps go, first you'll need a Power Commander fuel injection module. Then if you want a custom map you'll have to have it dyno tested, or find a Warrior owner with a similar set-up. There are a lot of guys on this site who have PCIII's and may part with one of their custom maps. The Power Commander website also has a bunch a maps.
Hope this helps.