So what I really and I am sure others want to see is double mutations like maybe
A melanistic Dwarf
Or a achromia Leopon
And my favorite The dwarfpon!
I think they would be more rare but you can find them in explore but you have a 1-100 chance to find them unless you use catnip then you have a 10-100 chance to find them.
I think they should be able to be bred but a 1-100 chance without breeding items but a 25~100 chance with a breeding item