Moped Army

So I have been on this site for about 2 years. You guys helped me get my Hobbit to where it is today. Now I ask whats the best path to take with upgrades. See, my hobbit does about 37 top speed. Thing runs like a dream. No problems what so ever. (Knock on wood!) But, I want to go faster...lol. Should I do a kit and a pipe? Whats truly the best config for a Hobbit/PA50II. I wanna hear some real stores. I have searched on here and found a few helpful things, but kinda want some up-to-date info. Thanks guys!