I always thought the Teletubbies were cute, despite being a little surreal. They were colorful and bouncy, with pleasant sounds, and seemed to appeal to tiny kids - not much different from the colorful and sometimes musical mobiles that folks put over a baby’s crib.
But my absolute favorite of the kid shows that I saw as an adult, was ‘Oswald’ - (probably for slightly older kids). Clever characters and story-lines:
https://www.youtube.com/watch?v=WDn2HkcW4jw
How about the abstract activity inside of SpongeBob’s brain?
https://www.youtube.com/watch?v=utwJ2c_zCaQ
Oswald was my son’s favorite as well. I have them all recorded on VHS for his son or daughter.
Next favorite was Oobie, then Maisy.