A recommendation: you mention the use of SVGs. I haven't looked into the code, but I'd recommend against using SVGs for the background images, but rather 720p PNGs or JPGs. Other than that no considerations. If that's not what you're using SVGs for, please ignore:)
I hope you add this to the es_theme installer on RetroPie Setup :)
@Noxoreos, never mind on that question regarding the directory (it just looked weird to me; I've never seen a folder with a ".data" at the end). Another question, however, whenever I try and run the shell script, I get an error about not having the permission to access data in the /var/lib/bluetooth/ directory. Any idea what's going on there? and how I might fix it?