i am playing for nearly 800 days and currenntly lvl 334, been for most of that time in 2-man guild so here is my point of view.
my thoughts on traitstones:
i have hundreds of minor and major traitstones and in general <10 of runic and arcanes (except yellow runics, those i have plenty but everybody know why 
).
i trait my troops mainly to power up kingdoms, but at this point i traited every common and rare twice, ultra-rare once so i wont have a big usage of minor and major in nearest future.
this disproportion is not looking good, no wonder that every day on this forum pops up new ideas to make crafting a reality.
i would like to suggest another answer on this problem: lets make in options a choice to dont gain those low tier traitstones to get a bigger chance to gain those rare ones. something slim, maybe +1,75%.
i had a feeling that this post could be shorter, but i take this oppoturnity to practise my English 