Here are my thoughts on some of the characters who dont have all 3 stages for best/worst yet.
Donkey Kong
Best: Brinstar, Jungle Japes
Worst: Frigate Orpheon, Rainbow Cruise
For DK I would put his 3rd best stage easily being Luigi's Mansion, his ground pound is vicious here.
Ice Climbers
Best: Final Destination, Smashville, Pictochat
Worst: Rainbow Cruise
For Climbers I would put Norfair as one of the Climbers worst stages, Platforms maake it a bit harder (though not to much) for them to get there grab, and alot of characters with disjointed hit boxes will outshine them here.
Marth
Best: Battlefield, Delfino Plaza
Worst: Brinstar, Jungle Japes
For Marth... Marth likes Platforms so I would honestly say that Final D is a not so great stage for him, Marth easily adapts so its hard to CP him, but I would go FD.
Ness
Best: Delfino Plaza, Brinstar, Pirate Ship
Worst: Yoshi's Island, Yoshi's Island (Melee)
I dunno what the everyone else thinks but I would say Luigis Mansion hurts Ness...
Snake
Best: Norfair, Halberd, Smashville
Worst: Jungle Japes, Rainbow Cruise
I personally would say that Lylat is better for snake than Halberd...but thats me.
Wolf
Best: Smashville, Yoshi's Island
Worst: Lylat Cruise
I would think Frigate Orpheon would be bad for Wolf because of his awkward recovery and the lack of grabable edges.
Feel free to discuss or disregard, lol.