Of course there is potential. The Mario Kart 8/Yoshi's Woolly World is the perfect way to use amiibo. Amiibo should be more about unlocking minimal fanservice stuff that doesn't affect the completion of a game but mostly gives you something based on the character that you bought.
Amiibo shouldn't be a Pay to win. Having that in Rainbow Curse and Paper Jam for me is an unsatisfying addition.
Shovelknight and Splatoon are doing it wrong too... unlocking stages and challenges makes Amiibo look more like a download key than something new.
Not to mention Mario Party 10 or Amiibo Festival, turning amiibo into just a simple button. Talk about grasping the bottom of the barrel.
Smash Bros and Mario Tennis have a pretty decent idea, but doesn't feel new or needed enough to be a thing bigger than the figures themselves.
As I said, amiibo should be mostly for skins and small stuff, but it also should have it's own centric game. Something huge. Amiibo needs its Disney Infinity, its Skylanders. Heck, a sequel for Nintendo Land would work perfectly with amiibo.