Just as a request to keep people safe what you should do is a have some popups for people to use metamask on the site instead of exposing their private keys to you. This is, without a doubt, going to help in making people feel more secure on this site (even if your main goal isn't to get customers, it's just to have a little hobby on the side)

I must say this is pretty cool though, may I ask what code you're proficient in? I may have some work that I may need done, unrelated to Bitcoin completely but I am looking for some coders.