Final Destination is not, and has never really been, a balanced stage.
I long for the time when this argument is put to rest.
No stage is "balanced", furthermore the degree of "balanced" is subjective to our individual opinion and is the root for every never-ending debate about stages to be used. This essentially comes down to an ad naseum argument and to keep this from being off-topic and moved to Stage Discussion thread I think I'll leave it at that.
It favors characters who like having alot of space to maneuver and hinders characters that rely on smaller spaces, who typically need platforms for their approach options. This is why, more often than not, most people will call Battlefield or Smashville the most balanced stages.
Competitively speaking this is why a competitor should use a character that takes advantage of the stage if they are going to be using it.
Also, is there not a hazard on Smashville which gimps recoveries and nullifies projectiles (balloon), therefore it isn't "balanced" and shouldn't be used.
Would a hazard toggle get rid of the balloon? (the moving platform can be argued to be more of a "hazard" yet).
A stage hazard switch would open up stages such as Warioware, Jungle Japes, and Brinstar as competitive options.
Ultimately I do agree with you, but now the conversation has to evolve into nuance. Would you say the water in Japes is competitively viable? Or saying that water should be considered a "hazard" and removed with the hazard option?
And is Brinstar's breakable objects considered too "unbalancing" to allow (certainly if FD and a little balloon are unbalanced then this would disqualify Brinstar).
Additionally, would the Warioware games still should reasonably happen (but without the "hazards") if other dynamic stages are allowed.
EDIT: Saw you addressed the question of water. But should non-hazard mini-games & breakable objects still be in a "non-hazard" version still remains.
And to the point of how much it really matters, because the hard fact right now is we don't have a no-hazard option, so is it something we must request a patch for or seek to hack P:M style? We don't need those stages to play the game competitively, obviously, as it is being done so right now. It could be argued for the sake of aesthetics or just the novelty of something "different", but is that means to justify a goal?
This analysis reduces to opinion much like the "balanced stage" subject, and subjectivity of balance and such is the realm of the game designers. We are not the game designers, Sakurai (et al) would be, so ultimately I have to just accept the game for how it is. So maybe address this to Sakurai (and I pointed out it was, and he gave us Omega versions) or direct and design your own game much like the P:M team did. Sounds like it could be fun.
Final point of interest if Hazard Toggle were the case: There would most certainly be the case that these stages would be "banned" still - just look at how Omegas are "banned" and how certain ones are questioned for being allowed due to walls of stage extending down, differing shapes, non-wall jump areas, light/dark issues, background, and probably some more issues I am unaware of. Ultimately someone somewhere is going to want to ban a stage for any difference claiming "unbalanced" which is where I believe Sakurai came to the decision to give us Smash "fanatics" the one Stage we (publicly) worship: Final Destination only.
Agree with him, disagree with him?
As for my opinion, I'm ambivalent, I play competitively so I just play the game and have more fun that way.