Oh! I think I may have figured out something neat.
This "Ink Drop" thing everyone's going on about...you say that if you dash for a while in one direction and then try to turn around, you trip instead of actually slowly changing direction like in Melee? Well, look at this video:
http://www.gametrailers.com/player/26689.html.
At around 1:35, Mario dashes towards Kirby, stops almost dead in his tracks, and immediately f-smashes him off the stage. I was thinking that maybe this "dash brake" sort of technique is done by holding the opposite direction you're running, and that an "Ink Drop" tripping effect is actually supposed to be the
punishment for screwing it up by holding it for too long (though the trip appears to have some wacky utility of its own). This could be a new spacing mechanic they added to help make up for the loss of wavedashing (granted, you can't do it backwards or in short distances, but hey, it's a new kind of approach).
Forgive me if this has already come up, but it struck me as being really interesting, and it could be something to look into over the next few days for you E for All attendees.