I can say Gintama is the jestiess* series I've ever read. Every character is made a mockery of, and your perception of what "type" of character they are, is thrown out the window. (its funny because the voice actor interviews say they had troubles portraying their characters)
Lets imagine your favorite anime character. Now imagine your character being made fun of into oblivion. Maybe your favorite character is the "serious cool type", (Yato, Kirito, Sora, Saskue, L, Lelouch, Kaneki... whatever etc). If these characters even mention the that they need to take a dump, or something silly, it kind of ruins the "image" of the character.
Gintama just does not give a shit. It will take a well designed serious looking character, like Takasugi, and dub over his lines with a squeaky voice, and yet, IT WORKS. Gintama knows when its time to joke around and when its time to shift to a more grim darker tone.
Gintama has kind of a slow start. We want to see plot progression towards a goal, advancements, go go go! But Gintama isn't so much about attacking, but rather defending and protecting. How most narratives are written is "character vs the entire world", which is alluring to us because we have dreams and goals. How Gintama is written is that our characters are dealing with the aftermath of failed goals, such as a lost war with the amanto(aliens), instrapersonal struggles with the past, and so on. It may not seem like it since most of the series is masked in comedy, but it is there. The comedy is sometimes hit or miss.. forgettable, not funny... wtf.. I found myself in the beginning rolling my eyes at the dumb jokes(zura, fruit punch samurai g, mayonaise) and lack of direction but later on finding myself embracing the jokes and loving the lack of direction.
Expecting and wanting plot progression and rapid action will leave many to prematurely declare the series has no charm, but really, you just gotta let go.
