Murlough
So you think that Miis shouldn't have access to their specials because it would be "unfair" to the rest of the cast, right? Assuming "unfair" means "broken/overpowered/unbalanced" (which it should because tier lists exist, etc.), there's an easy way to solve this: allow Miis their specials and see what happens. If they suddenly start beating or going even with every character, or if Sheik players drop Sheik to play an unrestricted Mii and maintain their dominance, then you're right. Something is wrong. Then we start restricting.
The data that
does exist (EVO 2015, MLG, Shots Fired 2, BEAST VI, most of Europe and pre-EVO 2015 NA) is in favor of the null hypothesis here: that Miis aren't OP or "unfair". However, this data is not frequent or relevant enough (except maybe Shots Fired 2) to prove anything on its own. That's why Miis should
at least be allowed testing. So we can
know if their impact is negative.