It's very possible that the way the Tower of Smash is set up resembles a board game? I mean, if it does, you could move up the floors along little "spaces."
Also, like someone said before, Classic Mode resembles a board game now. That was literally the first thing that came to mind when I saw the redesign. And, there was nothing about the new board game mode being the "big thing" or the "single player focus." Not even close. Not to mention that Classic Mode is basically the biggest single-player mode, along with All-Star, now that Story Mode is scrapped. To be honest, though, I do find it slightly strange that he didn't mention as Boss Battle mode like the ToS leak mentioned, but then again, he didn't say anything about Multi-Man Smash or Home Run Contest or anything, and since those are probably grouped together in the same category like in Brawl, I would say it means nothing.
So, yeah, ToS leak still looks very possible.