Adaptation Displacement: Western fans know of the series mostly from the Akira Ishidanote Not the voice actor, mind you. manga version (the one running in Comp Ace). When the character designs for the anime adaptation where revealed, some complained that they didn't look like the "originals" at all, when actually they are pretty faithful to the Light Novel version.
People's titles must change with time. Head Maid must at one point have been New Maid (or something similar), and Female Knight must at one point have been Female Cadet. On that note, how would you differentiate any number of people with similar roles? Do you append numbers or adjectives to the given people?
In the LN, people with similar roles are not even given numbers. Characters do have names, but the author said the readers are not allowed to know them or supposed to be interested in names.
Hollywood Pudgy: The Demon Queen. It's worth noting that she's the only person who thinks she's pudgy. Certainly made a Double Subversion by Head Maid, who consistently calls Demon Queen's breasts "useless meat." She laments that Demon Queen has a sexy body but a poor mindset to go with it, and eventually flat out states that Demon Queen's "useless meat" will only stop being useless when she acknowledges her worth and puts it to work (ostensibly to seduce Hero).
Magnificent Bastard: Young Merchant cooks up a plot to trick Central into selling all of its wheat to Union, which he then plans to hand over to the Southern Nations as an investment in their rapidly expanding economy. This also has the side effect of destabilizing Central, since a combination of wheat shortages and inflation means sky high prices for food. He also plans to destroy financial trust in the Central nobility when they inevitably fail to pay their handover bonds, demolishing any attempts at Central to start up a new currency system to counter the inflation. The only people outside of Union that catch on to this are Hero and Merchant Youngster.