I think it's a really good start, takes a bit getting used to the style, but I enjoyed playing the game. Did get a bit fed up with the Reaper so I haven't defeated him yet. But overall I would say you're on the right track!
Now that I've played it a few times I think toning down the frequency a little bit of what our friendly bunny says might be good, especially when killing enemies. Or have more different sounds, maybe a mix of a bit shorter sounds that happen more often, with snarky things every now and then.