Please consider the addition of a "Generic" category of color symbols that we may attach to text/number columns for personalized categorization driven by formulas, etc.
For colors, I would recommend a standard ROYGBIV plus black and gray.
For symbol types, I would provide the above color scheme for circles, squares, stars and triangles at a minimum.
If the code modules for symbols are easy to duplicate and adjust, and we cannot have the capability to create our own symbol sets, this would seem to be a suitable compromise to provide the users with a flexible solution in order to improve the UX of the platform.
Please let us know if this is a feasible request and if it is something that the development team will consider. Thanks.