What should I do after Insanity?

I'm 15 years old (female) and I weigh about 108 pounds as of today. I was never overweight I just wanted to tone up a bit, and I'm so happy with the results so far. I'm on my fourth week of the Insanity workout developed by Shaun T. and I plan on completing the entire schedule. I was wondering what I should do after I finish this exercise regimen as I'm aware that you can't just flop down and not do any physical activity and expect your results to stay.

I don't really want to go straight into another tape like P90x or anything because I want to stay lean and toned and I'm not going for that super bulked up look that most of the people use these tapes for.

I have access to a full gym and I can go running and biking and other activities like that.

I basically just need to know some light - heavy exercises that will keep me lean and fit without bulking up, but not losing the progress that I've made. :)

Thanks xx