Madara got too boring. He talked too much and honestly i saw it coming since he wasnt a true villian. Kaguya is a true villian exactly the oppisate of madara in almost every way possible. Ill be happy so long as madara doesnt return as final villian
He only got boring after he became juubi jin. Before that, his appearance was one of the most exciting(fighting an army, meteors, PS, etc.) it was epic.
Kaguya has hardly said a word and her only power is shifting dimensions which isn't exciting at all. If she keeps being the way she is, she'll be the most dull character in the series.
I've been saying this for a while, but Madara has been foreshadowed since part 1 and was relevant throughout series. He deserved to be the final villain.
As soon as he became Juubi Jin though, he became way too cocky and only used Limbo, which was indeed boring. Don't know why Kishi decided to do that.