Big D beat me to a lot of this. Yeah, we're pretty much dialed into that sentiment at least, as you'll see shortly. I'll lay out our thinking one last time just for the heck of it with a bit of history tacked in.
The original reason for having "neutral" starter stages at all back in the day was not because the plat stages were considered necessarily superior, but because we used a random select system for the first round. With limited stages and one ban each, logically the thought was that by doing this, you limit the effect of the randomness and give people an idea of what to expect during the first round so you don't get drastically swung matchups in round 1 in a situation where you had no control. While relative neutrality was a factor, it wasn't nearly that so much as the need for an expectation going into the match.
With the advent of the stage strike system, it changed the game. Now, you arrive at a median for the matchup every single time, without randomness. Plus, it is determined by the players themselves. Our thinking was that, logically, this should allow an expansion of the stage list to all competitive stages. With the randomness eliminated, and a median stage meant to be a representation of the actual matchup in the first round, logically that suggests that the more diversity in the stages you have on, the better the approximation of the median should be.
Of course, this suggests in itself that attempting to balance the cast is not of interest at all, and rather, the primary interest is to include as much variety in stage conditions as possible to test the widest variety of player skills. Whether or not you agree with this sentiment comes down to your philosophy of how you experience the game. I don't put much stock in which stage the Ice Climbers specifically end up on, just like I don't for Yoshi, Pichu, and Fox. If they're viable characters, the median stages will work out well enough, if not, they won't, same as it does under a MBR5 ruleset.
I totally admit that it’s an idealistic view about the game, and clearly there are "risks" involved, if you want to call them that, of top-tiered characters rising to dominance. Yet, there was no evidence of that in the past and no one stepped up to the plate and provided any, so it's hard to consider it as more than theorycrafting. I believe that trying to force balance with rulesets is a bit silly, as we've just discussed, because so much of it is opinion-based. Even in this thread, there have been disagreements on if this ruleset favors space animals, floaties, or people who change characters freely. I'm going to go out on a limb and suggest that the ruleset would've probably favored the player who was playing the best that day.
Ultimately, Smash is a platform fighter where stage variety is a huge aspect of gameplay, but at the same time, it also gives us the option to change our experience of the game freely. If nothing else, I hope that this discussion has reminded people that it’s ok to think about the game differently, and that no single person or entity owns this game. We ourselves have run both 6-stage-only tournaments and 10-stage random select with 10 additional CPs tournaments. Going BF-only occasionally is fine by us, but if that’s your only experience of Smash, we think you might be missing out on the a part of the soul of what makes Smash unique.
Anyway, with everything wrapping up, I wanted to thank you all for the discussion. We’ll have the new rules up within a few hours. At that point, I look forward to turning our attention toward making FC into the Best Tournament Eva’, yet again, and we hope you’ll all be there.