The Superhero Database Classification number, or SHDB Class, is a number that represents the overall 'power' of a character. All traits of a character are used for calculating the Classification.
What it DOESN'T mean
This doesn't mean that a higher class would always beat a lower class character. But the bigger the difference in Class is, the more obvious it is who'll win in a fight.
How is this calculated
( INT^1.3 + (STR*0.5 )^2 + (SPE*0.5)^2 + DUR^1.6 + (POW + (SPS*SPL))^2 + COM^1.8 ) ^ TIER
Super Power Score and Level
Every Super Power has a score (SPS) that is used to calculate the Class. Each Super Power also has 3 levels (SPL). The level is set when connecting that Super Power to a character. The level determines the final score, of the Super Power, being used in the calculation.
as far as Loki becoming the god of stories and was only able to negate a retcon from one writer within the Marvel universe. he is anyway confined to the house of ideas. but his plot-based abilities are limited in that he can't lock a beyonder's avatar into yesod/beyond in narrative arc.
Featherine is stated to be the author of the entire Umineko story and can edit/modify it at will, allowing her to do anything including defeating other characters as Lambdadelta just by narrating it. and exists on a higher metaphysical plane than even the layers of the Witch Domain in Umineko. She essentially views the entire setting as a work of fiction, which she can freely manipulate and rewrite.
The House of Ideas itself would likely be beneath Featherine's notice or influence in her true form. She could view and affect it just as easily as any work of fiction in Umineko. in her true form she become a Creator on par with the supreme beings known as Creators in Umineko Lore. Transcends all boundaries and restrictions, including their own 'meaning' and 'will'. ,Creators control and encompass concepts like zero, one, infinity and all possibilities - including all impossibilities from any perspective. described as the status of an omniscient and omnipotent Sacred Being, free from all restrictions including concepts like life, death, existence, duality etc.