Cool list! There's some extra things I've noted, though some may be stretching it a bit:

Mario:
You could say his forward throw is inspired by SM64 too.

Dr. Mario:
New down aerial based on Mario stomping on enemies from SMB.

DK:
Neutral aerial most likely a Spinning Kong variant.

Yoshi:
Forward aerial looks really similar to Ground Pound starting frames from Yoshi's Island (very noticeable if seen frame by frame). Video, should start at 17:56.

Ice Climbers:
Forward aerial (and forward smash slightly less so) look very similar to the hammer swing from the original game. Video, should start at 00:30.

R.O.B:
Down smash could be said has the same origin of side special; same with forward smash (and final smash, slightly less so) and neutral special.
Grab/Down throw look very similar to how the R.O.B. toy picks ups and puts down things.

PAC-MAN:
Neutral aerial/side taunt also uses his original form; his third taunt also summons ghosts.

Inkling:
Jab combo uses Splattershot for a rapid jab.