There should be some redistribution of traitstones in kingdoms. For example, Arcane Beast traitstone can be farmed in only one kingdom (Wild plains), while Arcane Lava can be farmed in four (Urskaya, Grosh-Nak, Sin of Maraj, Hellcrag). For the sake of variety, please try to distribute traitstones more evenly throughout all kingdoms.
Note that this is … kind of not an easy thing to change.
By design, every Kingdom has one or two associated Mana colors and this dictates:
- The color(s) on the Kingdom Banner (note it’s technically possible to have 13 Kingdoms using the same two Mana colors without actually duplicating a Banner)
- What color rewards you receive from Challenge battles (Traitstones in Tier IV, crafting Jewels in Tier VIII)
- Which Arcane Traitstone you can farm from that Kingdom
So from a design standpoint, if you change one of these you need to change them ALL to match.
However, maybe an alternative idea – compare that Celestial Traitstones can drop from any color Kingdom (because they are “all colors”), so what if:
- When you defeat the Explore Mythic Boss and get that guaranteed Arcane Traitstone drop, the other (normal/random) Traitstone can include Arcane Traitstones matching any one of the Kingdom’s colors. (e.g. so in Whitehelm, you are guaranteed the pure Yellow Arcane Traitstone but a second Traitstone, if Arcane, could be Yellow+anything).
Thank you for the answer. I didn’t know associations between kingdoms and colors work like that. It’s a food for thought 
Now from a technical level it doesn’t have to work like that, it’s just a design pattern to help players out – so it’s kind of important to be keep it consistent and predictable.