Quoted By:
Most of those have good to high placings on polls.
Only ones that aren't are Meganium, Emboar, Chesnaught, and Rillaboom
Wouldn't call Meganium a flop as I doubt the designers ever thought it would be something cool and widely popular especially with its moveset.
Chesnaught looks cooler but was not given a lot of focus in favour of Chespin, which was intentional
Emboar and Rillaboom were the only two where I feel like the developers expected people to like them.
The Emboar line has a ton of focus in the anime that never went anywhere likely due to the fan response to Emboar.
Rillaboom was similar to Chesnaught in the anime until the Masters 8 portion where he got all the spotlight to himself in nearly sweeping Diantha. He was also given extremely strong moves and was even made the grass partner for the Hatsune Miku collaboration (his artwork had gotten the least amount of attention).