Ask your kids. I ask my youth kids and they gave me a list of about 10-15. Of course they're all popular/mainstream and used in a lot of other routines (Applause, Roar, etc.), but if the kids want it in there, they're going to be more excited to hear the music. I put in 3 of their chosen songs and added in 2 others that went with the feel and they loved it.
I personally also love when teams have themed music. I find you can get some really creative music mixes then with a lot of songs that I wouldn't normally consider for cheer music.