Not really a bullet hell player, so I think that's about as good a result as I will be able to get, at this point things were just getting way to frantic for me, but I certainly had a blast playing your game, it has a really addictive quality!
I had quite a lot of coins at this point so wanted to give the last gun a try (was still on fully upgraded pistol at this point after having tried the assault rifle in the previous round) but didn't survive to get back to the shop. Might have to have another go to check it out.
I can't really offer any suggestions for improvement, everything was great! Music, graphics, atmospheric lighting, the juicy gameplay, particles, blood spatter, all just came together nicely here. A minor point might be that the dash mechanic didn't feel that natural (I was hoping I would dash in the direction I was moving, but I think its in the direction you're facing which usually meant dodging into bullets etc.). Also it would be nice if there would be more indication when the player takes damage, often I would be surprised to see that a chunk of my health was missing but that might just be the fast pace of the gameplay.
Fun game!