If Shovel Knight gets in due to the ballot, I think that would just about confirm that Sakurai doesn't have a say on who gets in from the ballot, and that he is required to make the winners no matter what. Sakurai would do anything to get around adding a character he has never even heard of . He's very protective about who makes it in Smash. I always kinda presumed that the higher ups at Nintendo essentially told Sakurai they would make the ballot with or without him, and he decided to stay to protect his idea of Smash as much as possible. I could never see Sakurai willingly start a ballot where people essentially tell him who to put in.
My thoughts on Shovel Knight being in Smash are mixed.
All the 3rd Party characters currently in represent something important in gaming history. Sonic represents the first real rival Nintendo ever had. Mega Man represents third parties starts to develop stellar and legendary titles for Nintendo's platforms, and other platforms too. Mega Maj is also a big influence to many platforming games that would come later. Pac-Man is...Pac-Man. 'Nuff said. Ryu represents the dawn of fighting games. Without Ryu, we might not have even ever had Smash.
I guess one could say that Shovel Knight would represent indie games becoming a big thing in the gaming world, but it's not like Shovel Knight is super important to the rise of indie games. A big figure that would represent that well would be Meat Boy, or even Commander Video (who, might I add, was given a trophy in Smash U for the specific purpose of representing indie games), but then again, neither of those could possibly have a moveset of any kind in Smash. So it seems like Shovel Knight would be the best option to represent indie games, given his popularity and moveset potential.
All in all, if Shovel Knight gets in, I will buy him (I'm buying all the Smash DLC), I will enjoy playing as him, and I might even main him depending on his moveset, but something would always stick out a little bit.