Speaking of Lip, I'm surprised there wasn't a Lip Mii Costume in Smash 4.
You could have had the Mii Fighter wear equipment that starts you with a "Lip's Stick".
i felt like the whole custom moves / and mii costumes were a really poorly thought out concept that actually had a lot of potential.
basically they could have NOT given every character customs and spent all that time making a bunch of mii custom moves, make lots more weights and size variants for mii body types (like a huge bowser sized mii body type, to a tiny kirby/olimar sized one) and then made the mii "costumes" actual new renders for characters and not just a good looking body/hat with the off putting mii face and sizes. basically a REAL character creator with the backing of actual pre-rendered models for requested characters, but they have pre-set moves from a very large list of mii custom moves (because all those customs they made for everybody would have instead been time developing tons and tons of mii custom moves) that way we could have actually basically gotten geno/k rool/ashley/tails/heihachi etc... and people probably would have liked mii's a lot more since they were an easy grab-bag of hitboxes and attacks to create other characters from.
i dont know how realistic what im saying could have been but it always felt to me like they had the idea of custom moves and mii's and it wasnt thought threw fully and they spent a lot of time giving everyone tons of customs no one ended up using much while also failing to make the mii's customization all that appealing to anyone either... if they had combined those ideas more fully i feel like they could have made a lot of basically low-effort versions of highly requested characters, slightly better than what we got with mii costumes and they might have actually made some people happy to be able to play as those characters. i never felt like playing as a mii costume version of a character really satisfied that itch of wanting to play as that character for anyone, but i think it COULD have had it been a little bit better.