Tried normal and lunatic mode.
First of all, an ex-boss battle for the catfish is by definition awesome. The last card's name puts it very well. :V
Though, as always, I will focus more on the negative parts because that criticism is always the most important for self-improvement, I believe.
The main problem with the script, in my opinion, is that the graphical effects, namely the glowing and transparency of the bullets but also the lasers in "concerto of the earth fish", sometimes become very distracting or start to obscure the bullets. Large amounts of round, glowy, translucent bullets merge together optically and become a mess where you can't tell one bullet from another. This makes some forms on lunatic mode basically unplayable. This goes especially when adding more glowing lasers to the mix, especially when these move at very high speed, which is another problem on lunatic: some of the aimed lasers are just too fast to react, at least when they are obscured by a sea of glowing bullets.
So yeah, normal mode is fine, but lunatic definitly needs a graphical revision. Didn't test the hard mode, though.