Hi Elliott, This is a great breakdown and very generous in sharing your process and insights, you came a long way from the vending machine days!
Are you planning on releasing the UE4 project to the public? Or only builds? I'd love to play around with it in the editor if possible!
Take a look at a free pack of 257 materials by Ruslan Nazirov with base colors selected in accordance with material design color palette guidelines. The pack is perfect for quick level prototyping and stylized games
Want to try creating your own materials? You can find color palette guidelines here.
- open the project;
- select MaterialColors folder in Content Browser;
- right-click on it;
- select Migrate;
- choose the destination of a content folder of your project.