The difference with say Street Fighter is it is all pre-planned, there's been on the disc DLC, and lots of cheap money grabbing moves.
With Sakurai and Namco Bandai, it wouldn't be pre-planned. It would be like "oh, the deadline is here, and we didn't finish Roy." "Hey, let's make him free/cheap DLC!" That way, we don't lose that content, and maybe a Smash game could get released after only two delays!
I trust Sakurai to use DLC to make it worth our time. Plus, I'm sure there'd be say a Season Pass for all or nearly all of the DLC. I'm also sure we wouldn't have to pay for DLC for things like alternate outfits, too.
Oh, and patches and glitch fixes will definitely be 100% free.