Actually, the thornax launcher is my favorite. It was simple, effective, and it was nice to have a small launcher instead of the giant, bulky ones that we got in previous years.
The worst would be the squid launcher because I could never could get those things to work. BIONICLE.com actually had to put up a video showing people how to use them. Also, while it did fit the underwater monster theme, squids as amo always seemed silly.
Quick question too, would tridax pods be considered blasters? They did launch objects and were the Makuta Phantoka's gimmick.