Pros: the idea of imaginary friends becoming real is just creative and amazing
The characters are whimsical and memorable
The artstyle is nostalgic
The “it’s hot in topeka” quote
Cons:
The episodes are sometimes cruel and annoying (basically that surprise episode and the bendy episode)
Bloo used to be a snarky but caring friend in s1, but the later seasons made him annoying and selfish
The finale sucked