I personally think I would become a better person with that much money. I am not a big spender at all, so I would save all the money (I might buy a nice piano and good Urtext sheet music, but that's about it) then try living frugally off of the money. Then, I can focus myself on the work that means a lot to me (writing my visual novel and music for professional engagements) and not have to worry about real-world money issues. It would probably streamline my work process by a lot.

I can also hire a decently-sized team to help realize some of my bigger (pipe dream) projects, like a private high school for pianists or start-ups from some of my tech ideas.