Awesome puzzle! Here are my lowest moves for each level. I think these are optimized but feel free to prove me wrong.
#1 - 4 moves
#2 - 4 moves
#3 - 8 moves
#4 - 5 moves
#5 - 9 moves
#6 - 9 moves
#7 - 8 moves
#8 - 16 moves
#9 - 9 moves
#10 - 23 moves
#11 - 14 moves
#12 - 15 moves
#13 - 9 moves
#14 - 15 moves
#15 - 17 moves
#16 - 19 moves