I think S.M.A.S.H. was canceled because both it and the Guardians Of The Galaxy franchise as a whole are pretty much Fantastic Four substitutes. Using their characters and villains. Can't have 2 like that.
Good actually, well I'm at it, are the Guardians Of The Galaxy shorts online? It looks like WOW dropped Disney XD for some reason as I don't get it anymore.
I tell ya, when I first heard this one, I was sure that Superman was going to die. Bud Collyer's performance is really believable (full of pain and desperation). And Mason Adams was wonderful as the Atom Man.