Hi, new here. I don't care who is in Smash Bros, as long as I see the people I want the most *cough*LadyPalutena*cough*.
But I actually kinda can't see Ridley. To represent Metroid, I'd prefer one of the Metroid Prime Hunters more than Ridley. Ridley COULD be scaled down, but it'd be weird. He already appeared large in a Smash game, and is most likely the stage hazard for Pyrosphere. And it'd not like they could put Kraid in Pyrosphere, it's RIDLEY'S arena.
The reason characters like Bowser, who are depicted large in most main series Mario games, is because in the sports games, kart games, party games, etc., he's depicted as normal-sized, making him canonical to his size.