A contact of mine was kind enough to compile these. The first image shows averages. The second shows median, and then mode.

This may explain why it is hard to land Agility-based potencies against level 1 enemies, and why it becomes increasingly harder to apply Might-based potencies as the levels increase.

Level 6 Reason and Presence are inflated by the psionic horrors (olothecs, voiceless talkers, Xorannox. Level 10 Reason and Reason is likewise inflated by various super-smart and super-charismatic monsters at this level, such as izyak demons, Aurumvas, liches, and the 4th-echelon War Dogs. Aside from those, Reason- and Presence-based potencies are generally a safe bet.

Stability, unsurprisingly, climbs as the levels rise. Level 8 stability is inflated by frost and stone giants (stability 10 is the iconic trait of stone giants!), while level 9 stability is inflated by fire giants and valok.