I do wonder if we will get something on the 30th. it seems we always get something big when massive amounts of fakes rise. I still stand by the that these 4 would be most likely (imo) if we were to get someone next update:
Wolf: Pretty much a given, popular demand, plus he doesn't need a new stage as starfox has plenty.
paper mario: Again, popular unique, from a hit series, and doesn't have to have a new stage, so he could be able not to throw off the 2nd stage theory.
Shovel Knight: mainly this is due to his leak, as well as the fact that he would be a very unique ballot character and a good start to Sakurai's " It will be nothing but fanservice from here on out" statement.
Bandanna Dee: If theories are true, bandanna dee could easily be a counter to shovel knight, and be a popular Japan pick, while also being fairly popular in the west. With him being a spear user, he could become popular from multiple reasons with those who aren't as familiar with him.
These would be my picks though, if we do get a new character on the 30th. Which hopefully happens.