First of all, I've tested out Link's speed and it seems to almost perfectly match Peach's instead of being truly slower. His speed might be around 1.40 to 1.41 at least, but not too close to Peach because it's almost.
And two, Link has a lot of reliable combos, sleeper. Bomb setups, D-Throw setups, U-Tilt setups, D-Tilt setups all into various attacks and aerials. Jab can go into Spin Attack, Boomerang into N-Air/F-Air, Bombs into F-Air, N-Air into a roll then F-Tilt/F-Smash or a Dash Attack, U-Air into U-Air, those three are just examples for Link's combo ability and are decent examples of his long library of combos.
You could always do that in the first place.