I totally see the greatness in the likes of I Love to Singa or One Froggy Evening. They both have simple, but memorable storylines that elevates them into one memorable piece. Along with Feed the Kitty and Puss n Booty, these are my favourite cartoons ever made.
I don't see however the exact reason why are the cartoons listed below are famous though:
What's Opera Doc? - nice, and artistically innovative piece, but the story is dull, the pacing is horrid, and the cartoon as a 7 minute MM doesn't work (for me at least). If Jones created a mega full-length anthology film like Fantasia, this would have been a solid Sorcerer's Apprentice type in-film.
Duck Dodgers in the 24 1/2-th Century - like the cartoon above, this could have been special if it had been an inner piece of a something bigger film. The cartoon has no proper start and no proper ending. The animation is innovative here too, but it is in the likes of Claws for Alarm as well, but they aren't hailed as something special by the critics. For me DD is just like a regular MM with the flaws mentioned above, and inferior to Drip-Along Daffy and Robin Hood Daffy.
Coal Black and the Sebben Dwarfs - while the two cartoons above are fine for me despite them being overrated, I actually find Coal Black as something utterly and completely unwatchable. Not funny at the slightest, not that I'm a big PC guy, just not funny. The storywork is a hack too.
Bully for Bugs, Baseball Bugs - regular sport/arena style cartoons... maybe my fault, but never been a fan of this style. Found these pretty average for most parts.
The Scarlet Pumpernickel - another mediocre cartoon with no proper point being in it, except featuring the first all-stars in the WB catalog.
Most of Friz Freleng's work after 1948 - not that they are bad, just not funny or classic. I love Freleng's work with Michael Maltese, but after losing him to Jones, he clearly went into uncreative mode. How on earth the likes of Speedy Gonzales, Show-Biz Bugs or Knighty Knight Bugs can be considered a masterpiece? No, they are not.