I like it when KK seriously posts =)
I'm glad I'm not the only one that thinks Pikachu should be quite a bit higher on the tier list though lol.
I think he could be better than Mario, Samus, and Doc. Maybe Ganon, but I'm unsure. I feel the top 8 are fairly stable right now, though. It would take some serious changes for me to want to drop Ice Climbers or Falcon below Pikachu.
This is kind of about Pikachu as a general character, kind of about Pikachu against Sheik.
Speed gives him the power to pretend to be a crappy Fox against certain range strategies. His recovery allows him to get away with taking hits from a few characters. The smash side-B with good DI on the sending hit really does change his recovery and prevent a lot of would-be loops from working on him. He also doesn't get automatically killed by very much. Sheik's chain grab doesn't auto-death him, which is kind of good (jumpable at 40). It's still like a 65% combo but I mean, it's not really uncommon for that kind of damage to be put out by other characters or himself. It also assumes he doesn't hit a platform and get it interrupted (which can happen on a few common stages... also, shyguys).
He also has a fairly good B-throw game on her recovery. It's one of the better escapable loops at low percents simply because Sheik poofing deep into the stage doesn't wreck it; Pikachu rolls back a lot when he throws and brings her to the edge (and more importantly, to a position where he can grab the edge super fast or respond to her DI and offstage options). Higher percents the increased knockback can make it easy to force poofs onstage to build percent for the U-smash KO (which is painfully early).
D-tilt has more range than her ground suite, which can be annoying.
His low percent combo game on her is similar to Fox's. He can U-throw U-smash from 0-40 or so (strong hit / semi-strong hit switches at some point) regardless of her DI. After, it always links to Nairs or Uairs, so you can play with her DI.
I think there's a lot of room for Sheik to grow in this matchup. It's not really one I'm familiar with and I've not explored Sheik the same way AXE has explored Pikachu. I'm also not as good as him as a player. However, that said, I am convinced it's not completely hopeless for Pikachu like I have thought in the past. I'm hesitant to say it's plausibly winnable between two equally skilled players because I still feel it's extremely uphill for Pikachu, but I think Pikachu certainly has enough tools to no longer necessitate a secondary for it.
Ganon's only real advantage against Sheik is the fact that his range class is similar on aerials and his chain grab goes to death. But the chain grab going to death assumes perfect conditions; platforms and nonsense really screw with it. Ganon has a better lag punish with chain grabs but again it's susceptible to platforms and other nonsense. Pikachu covers more options more effectively from the ledge during edgeguarding. Ganon's range I don't feel is a huge deal because Pikachu has speed where it's important and also has more range than her ground game. His Uair also eats all her aerials, which is good.
Thinking about it, I think Ganon is objectively easier than Sheik just because Sheik can hit Ganon easier and kill him from a chain grab (platforms interrupting are largely non-issue because Ganon can't really DI to escape Sheik's combos unless she's doing stupid combos). She doesn't really have to worry about anything being stuffed because of Ganon's low attack speed but she can stuff his moves because her range / speed ratio. She also camps him much better because of his large body and limited movement. A lot of that doesn't work on Pikachu very well.
I may be biased though... I would like to play AXE again.
