I set up adult Link against every character in Melee (save himself), everyone lv 9, computer controlled. I was curious as to who would win. Here are the final results of each round.
Link vs. Dr. Mario
Winner: Link
Link vs. Mario
Winner: Link
Link vs. Luigi
Winner: Luigi
Link vs. Bowser
Winner: Bowser
Link vs. Peach
Winner: Link
Link vs. Yoshi
Winner: Link
Link vs. D.K.
Winner: Link
Link vs. Captain Falcon
Winner: Link
Link vs. Ganondorf
Winner: Ganondorf (Hrm...looks like we're all doomed.)
Link vs. Falco
Winner: Falco
Link vs. Fox
Winner: Link
Link vs. Ness
Winner: Link
Link vs. Ice Climbers
Winner: Ice Climbers
Link vs. Kirby
Winner: Link
Link vs. Samus
Winner: Link
Link vs. Zelda
Winner: Zelda (So who should be saving whom? o_O)
Link vs. Young Link
Winner: Link
Link vs. Pichu
Winner: Pichu (That's a bit on the sad side.)
Link vs. Pikachu
Winner: Link
Link vs. Jigglypuff
Winner: Link
Link vs. Mewtwo
Winner: Link
Link vs. Mr. Game & Watch
Winner: Link
Link vs. Marth
Winner: Marth
Link vs. Roy
Winner: Link
Link won 16 out of 24 times. Pretty good, ne?