Danger Mouse - I think the consistent 4th wall breaking, kidnapping narrators, and sense of humour as a whole had an effect on my from a formative age.

Monkey Dust - the cartoon that made it clear to me that cartoons weren’t not at all nesseccarily safe for kids. I was too young to appreciate it at the time, it was too disturbing for tween me.

Sealab 2021 and Excel Saga both crazy animations that I found easier to digest about that time, too.

Watership Down, other folks have already mentioned.