My opinion and not to be so complicated Low Universe level: Characters who can destroy all the matter in a universe, or who exceed the amount of energy contained in the universe or whose feat is technically still quantifiable with calculations. Universe level: Character who can destroy the space-time of a universe, since there one enters levels that cannot be quantified with calculations. Universe+ level: Characters that can destroy universe/dimensions larger than our universe or that are directly infinite, it could also encompass those universes that have dimensions comparable to the size of the universe but that somehow continue to share the same timeline, for example those series that have a heaven and a hell but still connected to the main universe. Low Multiverse level: Character that can destroys multiple universes with different timelines or a multiverse with a small number of universes, perhaps a universe counts if it has multiple timelines, I suppose it is something...
