That is a false statement right there. Just play SK/RoA if you want to see what he can do.
Another thing to consider as a general rule; don't count someone out because you think they can't do much. Especially in cases where you might not be as familiar with a character in the first place. I think the Smash community has been proven wrong on this far too often as it is.
Remember these guys?




And they're the one's that don't do much. Shovel Knight on the other hand does a lot, so how can one say that he doesn't have much to work with?
It's wrong when people say it about Shantae, and it's still wrong when said of SK or any number of other potential newcomers. And that's not to say that it can't be true in some situations, but cases like those are fewer than you'd think. Afterall, with enough creative liberty even the unlikeliest of characters can work out.
Anyways, didn't mean to go so off topic there. Let's get back to Shantae stuffs.