On level 29 I didn't use the giants, just kept the fishermen. Since I didn't use giants, I didn't need the tambourine girl. I did take in boxes so that the tamer could reduce the enemies' armor right before my fishermen. I also took in frogs & bats.
I use the arrow keys to move the pieces and sometimes it is too touchy. I have trouble moving the piece just one click. The game also seems to reward you if you go slow since you don't get as many points & won't level up as quickly. Then you have more time to get rid of the danger pieces. Over all, it's a great game and I can easily play it for a LONG time.
Ugh! Twice I removed a stone by water and my hero moved too slow to get out of the way. Unfortunately, I was full up on energy and it cost me the A+. Not sure if it's my computer or the game, but it seems my hero does not want to move at times.