^ Yes, but a lot of the lines that popped up were from Earthbound proper. The odd ones out were the ones that referred to "you" rather than Ness. The sunflower line seems really out of place for what is otherwise a Mother 2 reference.

I'm still gunning for Lucas or Ninten as a hidden unlockable in Beta (though highly unlikely as Bandana Dee and Luffy are still W.I.P; the devs need time to touch them up), and for another Mother stage to be in the game.
As for Giygas himself I hope he appears as a boss. I don't mind a stage but I think his potential will be a little bit wasted, unless they really make it vivid.

This is a valid point unless the hidden Mother character was already coded and complete or also a non playable W.I.P. and was intentionally left out of SSC. For Luffy only the cosmetic stuff was really incomplete(I.e. sounds and stuff) I didn't here anything about BD being a W.I.P. so I don't know about him, but for the most part both characters seem to be about 80% complete at the least. So there's plenty of time to finish each character(not including who else they've got planned for Beta's release), especially if they plan on releasing it around November-December.

And even if this "hinted" Mother content doesn't make it into Beta, there's still the proper full version beyond that.

Well, in the stream they said they want to please everyone: The competitive smash players that go crazy about veterans, the ones dissapointed on Smash 4's lack of Kirby newcomers and those anime fans that were begging for Luffy to be in. If that's the case, then I'm pretty they just left out the Mother character so they could show off the right ones in the stream.

inb4 it was a teaser for a lucas assist trophy

If we're gonna have Mother assist trophies, it better be Wess shaking his butt on a dance that takes about 30 seconds to finish, after that, the opponents are all stunned, receive 50% damage and KO after a while.
Just like Lucas's Project M Smash Taunt.

That was actually in one of the oldest Dojos. Just without the stunning/damage/KO.

I know, though it was just Amigo except with less range.