Armada didn't lose a single match during pound IV there, and he states that Peach is probably too good on the stage. This alone should make you think that there is a slight problem.
If you don't think Peach / Jiggz are too strong there I suggest you pay attention to the recoveries of the cast. The two mentioned characters (or Yoshi / kirby
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) usually do just fine without the edge, while others often severely punished if they are forced to land on the stage with their laggy up b moves.
Just adding a new stage and give out an additional ban to make sure you don't get taken there, if the stage feels unfair is not the optimal solution neither.
Follow me for a quick example: Suppose we have five stages s1, s2, ..., s5 (the neutrals
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) that are allowed to be played on, s1 giving you a decent advantage, and s2 a slight one. s3 is pretty neutral, s4 is a slight advantage to me, s5 is fairly good for me. Now we add c1 which is hugely in my favor.
Suppose I win our first match of the set (where we striked to s3).
If I had a single ban, I'd ban s1, and our second game would be on s2, which feels about fair for your counterpick.
However adding c1 gives me an additional ban, so I ban s1 and s2, and your best bet is to pick the neutral stage again.
Of course this is a pretty special case, but it might happen (maybe not in a variant which is so dramatic as the one above... say we had c2, and c3 without additional bans. C2 favours me again, c3 is even better then s1 for you. So we would end up fighting on s2, instead of s1 for the second match). So why add new stages which are just in favor of a very limited amount of characters and gives them the option to burn away fairly neutral stages where the opponent has a slight advantage?
I feel having a set of stages which are fairly neutral in the first place is the best idea. The neutral stages + pokemon stadium (maybe KJ64) are pretty fine. There is a slight advantage for some characters on some of the stages, like Marth liking Yoshis Story, or Peach doing pretty well on Dreamland, but these slight advantages are pretty insignificant compared to player skill.