I can't agree that puff needs a readjustment from horizontal to vertical recovery advantage (though they can do that if they want to).
But you can't say she "heavily lacks" a vertical recovery. Rising pound is risky if you mess up, but if you practice, it still gives puff one of the best recoveries in smash (far better than, say DK, and Yoshi, who needed invincibility on his double jump to make up for his sucky recovery). While her godly aerial speed most obviously affects her horizontal recovery, it also gives her even more options in dodging enemy interception when recovering vertically. I don't do brawl, so I'm not sure just how vulnerable she is to spikes 'n stuff, but in melee the lingering hitbox of pound made it a very safe recovery.
I don't really understand what "it's not constructive for Purin alone to bring in other characters but going back to balancing out the cast, they all have reliable stalling, vertical & horizontal mobility / recovery", but, um, she can stall up above the camera, like, forever...
Puff's a'rite.
Also, I like what the PM backroom is talking about right now, how recovering should be riskier than edgeguarding.