It's fine to make everyone good, but you don't go through the process painfully patch after patch, slowly. The game would be miserable adding to the top Ike and Lucario one patch, Sonic the next, Falcon next, Mario finally breaks through, etc. Do a big massive ****in patch where everyone does stuff ALWAYS and then it's cool. That's a huge gamble though and will likely be filled with horrible design choices for the sake of being godly, and characters will probably switch from being "true" to their character and suddenly everyone has the same 0-death CG setup on all stages, everyone has a great projectile, everyone moves like Jiggs and Wario etc.
Either way, Ike and others need to stay out of there until the rest of the cast gets stronger. I'm fine with the Ike changes because even after getting knocked down, he's still really solid and there are characters who would love to be as good as him.