Scott - I don't have a lot of time this evening to write a good answer for you. But briefly.... You are developing a new product for a market you probably don't completely understand if for no other reason than it looks to me like a new concept in the music fan market. I suspect no one will take you seriously until you show them one. Resin casting and hand painting is the obvious way to test the market. No matter how you make the first prototypes you are going to have to demonstrate that they are "art" worth buying. You can create that art in a 3d modeler and at some point in the creative process create an internal structure of individual parts to which you assign specific colors. That will get you a set of files of parts you can send to the 3d printer for production into solid pieces that you can assemble to verify that your design models actually look OK assembled. It will likely take several more printing iterations to get a complete review model. In the interim you will want to be exploring available colors of printing filament to see how they fit artistically. I hope you have some artistic ability to do conceptual sketches of parts and their coloration.
Somewhere along the line you should try some experimental resin casting to have that skill set in your "tool box" It may turn out that your "alpha" prototype is a mix of resin, 3d and even metal parts. The building of that alpha prototype will enable you to have something with which you start a an effort to explore the market for the product.
Think carefully before you expose your idea to the world. Almost any musician with a serious fan base is going to have people trying to get a license from him to produce and sell stuff related to his productions. And they all have contacts in China who will crash an idea into production if enough money is waved under their noses. And yes, they are getting very good at 3d printing.
Understand that your work is copyrighted automatically as is any piece of original art. Learn your rights in this area. Also understand the use of non-disclosure agreements before you are ready to actually sell these products. These will protect you from a supplier or agent stealing your idea or important pieces of it and early fueling a competitor. And also the musician has copyright and trademark rights that can restrict what you can advertise and sell with out getting a license from them. Your development work doesn't sound like it will produce anything patentable; but you can visit that subject later if need be.
You are doing a product development here and the same general approach needs to be followed or if not, understood, whether you are a "company" of one or a major corporation.
Start sketching and getting proficient in 3d modeling. Use a favorite artist medium to apply and test colors. Study the possible variations of patterns and colors as well as abstract art techniques that might be applicable.
So much for now. Til next time, Ed Weldon