Vaporwave colours are generally light blue, purple and orange on black, which is why the choice of colours in the vaporwave theme... EG:
And, as such, I will not be changing it... Also note that the theme will be maintained to fix bugs or issues, but I have no plans to actively develop it as a "proper" theme. It was a joke/experiment that I did to learn about the new forum software themes, and I happened to quite like the result which is why I shared it with you all.
So, yeah, going to close this topic as it's not something that's going to be changed.