Funny, Kizumonogatari is technically is the prequel (why I’ve been waiting so pong to watch it) The monogatari series has the most messed up release order…but they make it work.
I didn’t watch the Chaos;Child prequal either (honestly probably would have been terrible), but I read the source material and since the Chaos;Child VN probably isn’t going to be translated…so I’ll take the anime.
And Gintama, I mean it’s a comedy, and comedy is subjective. After that many episodes then it’s definitely isn’t for you, but personally I love that type of humor.
¯\_(ツ)_/¯