Cool idea with the limitation. There were a couple of annoying aspects that if changed would have upped my enjoyment by a lot.
1. The powerbar was dictated by when you let go of the mouse button rather than the moment you click. That took me a few tried to notice when It wasn't landing when I was certain I had clicked.
2. The cutoff window when the arm would come back. I would have been happier if I had the entirety of the length I had achieved via upgrades would be used to full effect. Instead there was a cutoff winnow of a couple seconds before the arm would snap back and not allow me to collect all the precious goodies that were between the cutoff location and the crab. Kind of makes the upgrading not as valuable if you aren't allowed to use the entirety of the length.