So I just got my level 80 Ukon, and decided to try it out against my tp+100 tavitisma which has a slightly higher base damage.

Upheavals were regularly between 1.3k-1.7k with tavistisma at 100-130tp, no buffs same gear
Ukon upheavals were regularly between 2.3-2.7k o_o

Gonna record a log later of some more tests... anyone know why this happened? o_o