I've had good results mixing micro GHK for different results as well.
Since I normally have Kava in the evening, I tend to use Nene as my base. From there I add other Kavas depending on what I want or need.
For example, if I want sedating + balanced effects: 2 tbsp Nene, 1tbsp Mahakea.
If I want a "headier" effect, and am not too concerned about getting to bed right away, I might do 2 tbsp Nene + 1 tbsp Moi. Or, 1 tbsp Nene + 1tbsp Mahakea + 1 tbsp Moi.