Yo, what about the entirety of the 80s?
Dr. Slump, High School Kimengumi, Captain Tsubasa, Cat's Eye, Stop Hibari-kun, Fist of the North Star, Ginga Nagaerboshi Gin, Kimagure Orange Road, Dragon Ball, City Hunter, Sakigake Otokojuku, Saint Seiya, and Jojo's Bizarre Adventure, Bastard, Jungle King Tar-chan, Rokudenashi Blues, Dragon Quest: Dai no Daiboken, and Video Girl Ai are all hugely influential for their respecive genres. Some arugably moreso than any of the Big 3 (I hate that made up term but for the sake of convenience in conversation

given their influence on the big 3 and onwards to this day and engaged and MUCH more experimentation.