I usually like deep-lore stuff, but the lore in this show isn't deep enough to justify abandoning charming goofiness in favor of love-triangles, love-squares, and serious political drama.
Case in point: Meteora was not handled well AT ALL. The fact that Miss Heinous had a claim to Mewni's throne is given no weight or gravitas. Like two episodes after she's revealed to be a royal, it loses any significance because she turns into a mentally degenerated hulk-monster.
You wanted a nigh-unstoppable hulk-monster with a grievance against Mewmans?
You can just as easily conjure something like that up by having some random angry monster steal the wand for a little bit, then juice themselves until they get so pissed and incoherent that they go on a roid-rage-rampage.
And as far as world-building goes, the Magic High Commission is the highest-ranking office of officials in the multiverse. They are essentially the "gods" of the world, and they jobbed in late Season 2. What they did, essentially, is they put a ceiling on the power-creep halfway through the show, and that ceiling consists of people that are immature enough to render any lore-related seriousness moot, and cement the show as one that should just stick to the comedy, like Adventure Time.