(bonk!)
Speaking about Claw Machine wave. You should change how you design the claw.
I mean… just look at that picture. When the claw stop at the middle and have a delay time before “drop” the group of chickens, this is when Players are at a disadvantage, sometime they can’t clean the top row of group of chickens, especially is on higher difficult.
What the… 
Small fact: In “The printer” wave, when you stand in a position look like this when there is a row of barrier “scan” the screen, you will be died 100%.
Wait. When did the barriers can also be counted for “Clean Sweap” bonus, despite all Chickens are killed?