Dude, Mushroom Kingdom sux BAD!!! And NO, just No. Dreamland 64 should be like the only one to return. Maybe Hyrule for the n00bs. LOL
Dreamland 64 already made its return in Melee, so expecting it back doesn't make one iota of a difference. Hyrule Castle is the most popular stage according to the original Smash Bros.com poll on the original website. Noob stage? More like favorite stage.
How does the Mushroom Kingdom suck anyway? It could've been better for a character or two, but it was a lot of fun, and made the battles interesting. Having more than one obstacle without easily causing unfair advantage for anyone(except Ness, and that's literally it) made it definately worth unlocking. Congo Jungle was the only bad level in the game, but only because it had no obstacles, and that was the fun of the original. Surprisingly, because the characters are more apart in Melee, CJ was played much more. Probably because there's so many rediculously big or crazy stages, that some easy ones made it nice.
I love Dreamland 64 and all, but most of the Melee levels were boring to me. Moving levels =/= fun. Of course, that's my opinion and all, but some like Icicle Mountain made the fighting...well, wait, what fighting? Any character with a semi-terrible or terrible jump were screwed. Not to mention, that it doesn't even help the Ice Climbers in any way(besides the non-slipping) that makes a real impact on gameplay. I'm not saying I want a character's main stage to make them actually broken or anything like that, but perhaps a slight advantage that could really help. I admit that the non-slipping might be useful to IC mains, but how many people actually use Icicle Mountain as a main stage anyway.
Sorry about talking so much about Melee stages and all. I just want classic stages that allow lots of thought, and little abuse as is. It also would make sense why Sector Z was changed to the rediculously smaller Corneria.(in the first game, Link actually needed his Up B just to get off the Tail of the ship itself. DK might've needed it too, but I don't really play him much, so...)