Creating your own VSCode color theme is actually pretty simple. Like wayyyyy simple. A Visual Studio Code Color theme is just a set of JSON key-value pairs. The key is the type of object, and the value is the color of that object.
I created a boiler plate that seperates the keys value pairs into language sections. I also added comments to help you understand what key the value is changing.
Just fork the repository, and you are off to the races!
If you want to see what you could make, checkout out the color theme I created with this template, it is Here!!!!