>>29548793Cheren achieves basically as much as Blue did. Cheren was never going to make it to Champion no matter what, because the whole N/Ghetsis shit went down. They both settle as Gym Leaders.
Then there is Silver who does unofficially beat Lance outside of the E4, and he was a pretty strong Rival.
Wally gits gud only for his single final fight. People only like him for his sob story.
>>29548990Gen 5 characters tend to be really popular in general because they had a stronger focus on giving each Gym Leader their own little developments. They even had entire little cutscenes for them in B2W2 with Memory Link.
Also worth noting that Gen 5 was based on the USA, so the characters were more western and thus more appealing in the west. Characters like a punk rocker girl may have a niche appeal to Japan, but would also be way more appealing and attractive to westerners.
The only thing I will stop you on is Marlon. I absolutely fucking hate him, I have never met anybody who likes him. I have also only seen (very little) Jap art of him, and nothing western.
I'm pretty sure nobody likes Marlon, that lazy fuck. He's also the only Leader in Unova who DOESN'T really get any sub-plot/development. He just sort of fucks off.