Villager can actually gimp Link in a single combo from 0%, it seems. FThrow near the edge of Battlefield leads to a pretty near guaranteed kill with Slingshot abuse. Now, it's certainly possible for the Link to use DI to make Villager's life harder by requiring precise aim and intelligent reads, but once that FThrow lands the whole situation seems to be far more in Villager's favour than it is Link's.
As for Pikachu, NAir offstage definitely looks like a decent option. DSmash is pretty powerful, but only if your opponent is stupid enough to stay in it. (It can be escaped via SDI just before the last hit, but it's still safe on hit because they're in hitstun until the end of the animation even if they SDI out.) USmash is still one of the best in the game, it seems like. Good kill power, sends opponents off the top at around 130% or so from the centre of Battlefield while being relatively easy to land. FAir and DAir seem to have kill power as well, IIRC. Also, don't forget about Skull Bash! No-one ever uses that move competitively, but perhaps it might be possible to get a combo or read into a partially-charged Skull Bash? I wonder how hard that hits in this game...
Sorry this is sort of off-topic, but people are complaining about being unable to KO in a reasonable timeframe and I'm trying to suggest ways to get around that.