I enjoy writing for timpani and young percussion ensembles. I have written a few pieces that seem to work well. I do not write for drumlines, but this is due the the lack of drumlines where I live. Any full band music I write has some sort of focus on the timpani as a melodic instrument in one way or another. I am not a percussionist, in fact I am a trumpet player, but I enjoy writing for percussion. I know your post is over a year old, but I just came on line.