So what stages are used in tournaments

[Crazy Hand 2001]

for singles and doubles?

 

[KinGly]

It depends on the stage list but a couple of common ones are the nebraska 9:
Singles Stagelist:
2 bans

Starters:
Green Hill Zone
Battlefield
Smashville
Bowser's Castle (Alt.)
Pokemon Stadium 2

Counterpicks:
Wario Ware
Fountain of Dreams
Final Destination
Dream Land

and for simplicity sake more than anything some regions run middle 5 bottom as starters with middle five middle as counterpicks, sometimes removing Yoshi's brawl

 

[Rpggames77]

At the tournaments I went to the order was

Starters:
Green Hill Zone
Battlefield
Smashville
Final Destination
Pokemon Stadium 2

Counter Picks:
Wario Ware
Fountain of Dreams
Dream Land or Yoshi's Brawl
Delfino's Secret

like KinGly siad it depends where you are.

 

[Only a NOOB]

Yeah Delfino's and Bowser's are pretty interchangeable. Most regions use either one or the other, but not both. Usually as a Starter stage, but I guess there may be some regions that still use Final Destination or Dream Land as a starter instead?

Yoshi's Brawl and Distant Planet are mostly completely dropped by now, but sometimes one of them is used instead of Dream Land (or in addition to it as an extra counterpick).

No sane PM tournament scene (that I'm aware of) uses Yoshi's Melee, Castle Siege, Lylat or Skyworld these days.

 

[Crazy Hand 2001]

Why not use all legal stages?

 

[Only a NOOB]

Tournament Organizers decide what stages are legal, and can even rework the stagelist to show their own custom stage select screens, since it's a mod anyway.

Project M still has a constantly evolving metagame, and sometimes stage lists should be tweaked to prevent certain types of character advantages from becoming too powerful in certain situations.

Just because Project M has a lot more tournament viable stages than any of the other Smash games, doesn't mean that those options can't be refined further to provide even better overall balance among the cast and players.