I'm already on it. Initial thoughts from my thread:
8:2
Bowser (Pretty easy, not sure if he is 8:2 worthy though)
ICs (Y HELO THAR NANA K BAI)
7:3
Link (Easy to gimp)
Ganondorf (Easy to gimp)
Captain Falcon (Easy to gimp...)
6:4
Mario (Gimpable)
Yoshi (Fair out of double jump = win button)
Shiek (Meh, not too scary.)
Samus (Easy to juggle.)
Pit (Somewhat easy to gimp, air game non-threatening)
Ivysaur (Easy to gimp, easy to get pulverized; be careful)
Ike (Wonderful weight/fall speed for Jiggs. Try not to get hit.)
Lucas (Don't walk into a u-smash and it's reasonably easy. His uair and nair are decent though.)
Snake (...wait, wut?)
Sonic (It's pretty easy to trade hits with him any time you want, which will result in Jiggs winning the match.)
5:5
Peach (Meh.)
DK (He's like a Bowser that can bair you in the face)
Diddy (Annoying in the air, but Jiggs has less issues than most with his crazy ground game)
Zelda (Spacing around smashes and aerials all day...)
Zamus (Side-B, down-b, and uair are bothersome, but that's about it...)
ROB (Lives forever; Just don't jump into a nair.)
Kirby (Meh. Know his aerials.)
Meta Knight (Wait, am I serious?)
Falco (It's all about gimping his recovery. To Jiggs he's like a worse Fox with lasers.)
Wolf (Meh.)
Charizard (Don't get hit and it's easy.)
Jigglypuff (...)
Ness (Annoying fair, killer bair and uair. Easy to gimp.)
4:6
Wario (Lives forever, annoying aerial game, f-smash from the devil)
Toon Link (Most annoying aerials ever, recovery hard to gimp.)
DeDeDe (Stupid bair, mildly annoying projectiles that help your stale moves list manipulation.)
Olimar (Not that bad honestly, once you learn the spacing and approach angles.)
Fox (U-smash... uair...)
Pikachu (Annoying fight, almost impossible to gimp.)
Squirtle (WHAT IS THIS I DON'T EVEN)
Lucario (Annoying aerials, hard to kill, Rest a must)
Marth (Stupid aerial range. Random u-smashes seem to kill me too, plus up-B...)
3:7
Luigi (Nair priority, Up-B out of everything)
Game & Watch (Bair, dair, killer smashes.)
2:8
Mewtwo (******* u-throw and down-b. ******** bair and nair. **** Mewtwo.)