All demons have the Abyssal Pact Ritual, but the individual monster descriptions don't specify what level the Ritual is. The back of the book lists the Ritual as level 1. Am I supposed to believe that a level 20 Balor has the same level Ritual as a level 6 Babau? The level 1 Ritual only lets the strongest demon the Babau can summon be level 2, twice the Ritual level. That means the Balor can also only summon level 2 demons at best?
I was thinking the Ritual should be Heightened the way a Cantrip is, or maybe half the level of the creature rounded down. The higher level the demon, the higher the Ritual. Is this an oversight in the rules? Why would a level 20 demon only be able to summon the same level monsters that a level 6 demon could?