'A Glass of Warm Ed' doesn't have much in terms of plot. It's just Ed eating a lot. The fact that he almost ate Jimmy was funny, though. And the part where Edd and Eddy stayed over at Ed's house was sweet.
The animation style appears ugly and childish but is in fact extremely sophisticated. Not as smooth as in the second season but much more interesting than Family Guy or Bob's Burgers. The characters have volume and presence. You can see that in the scene where Eddy clambers onto Ed's stomach. It all feels tangible and three-dimensional. The characters have wavy outlines because the creator noticed people made little movements even when they were doing nothing, which is incredibly inspired. The characters are definitely easier on the eyes than David Jason's BFG. Nothing gets me more invested in a cartoon than good drawings.
It can be argued that the Warner Brothers cartoons were somewhat "ugly", too. They did capture human expressions that simpler and more contemporary cartoons wouldn't have dared.
The timid, bug-eyed Edd is just adorable. He reminds me of some character from a classic film or cartoon.
I love how Eddy is not a morning person. I can relate to that. When he gets rudely awakened his first line is "Who turned off the sun?"
As for Flea-Bitten Ed, I used to get somewhat annoyed by Rolf. I thought he was just an Indian stereotype. But on a second look I find that his accent is less Apu Nahasapeemapetilon and more Wally Walrus. He's from a foreign country but it's never made clear where. Anyway, he's one of the characters who's based on Antonucci himself; Antonucci is Canadian of Italian descent. His parents were first-generation immigrants, and his family would always come out with strange proverbs. This childhood experience made up part of Rolf's characterization.
Ed floating in the air recalls a Three Stooges gag where Moe gets his suit filled up with air and starts floating.