Thank you for the detailed feedback!
I'm planning on taking a look at optimizing the gore and explosions a bit more in the future, but at the moment, the graphics options give you options for simpler explosions as well as how much blood you get per hit in case your performance gets real bad.
The problem with the Cerberus fight is that its difficulty is incredibly split -- For some people who had trouble with Swordsmachine, they get Cerberus with one try, for some others it takes over 20 to get it down. It really depends on how much you've gotten used to the movement of the game and when the right moment to go in to heal is.
Balance changes will keep happening overtime, though. If a lot of people find Cerberus too hard, I'll ease the fight up a bit.