It would be nice to have some control over the targetting system. So you can decide if all fishermen need to target the same fish or all pick another one if nearby. Also the option to turn on/off switching to another fish if it gets closer then the one that's currently targetted. It can be annoying to be chasing a fish only to have another one targetted just because it's closer.
I found a weird bug in level 12. Everything's fine, untill I buy 2 doctors. Then Tesla, Stalin, my towers and the enemy towers all stop firing and they just walk to the exit. The camera stops following and I can't move the view, not by mouse or keyboard.
The numbers of moves for par aren't checked properly. I played about 35 levels and did it in at least 5 levels in less moves than par. Good game though