I'm glad you liked it! Yeah, I totally underestimated how much work it would be to balance the different ships within the time frame. The fish and triangle ones are probably the easiest to use because they are fast which, in a shmup setting, is probably way more immediately useful than strength (which the other ships offer at the expense of speed).
The green one has a reticle that moves back and forth and you have to press Space to blow up anything in the little square around the reticle. It's probably the hardest one to use and its the least polished design-wise since I added that one later compared to the other ships. I even specifically programmed that one to appear less often for that reason, haha.
Thanks for the feedback!