No they had small roles. Because they were weak when the story progressed so didn't play a major role.
Kaido shanks and blackbeard will die for sure. Big Mom maybe maybe not.
There won't be twists for the sake of it. They are still top tiers they are too strong to be a crocodile or a Mr 3 or a bon clay etc
it's not about the power it's about the method man ...
and Oda method is about upcoming
throne war
there is no reason to assume the promised throne war won't come simply cause it might be too much for people imagination to handle
Teach is on the move
Shanks is on the move
Dragon is on the move
Imu is on the move
ending of one piece would be determined after
throne war and assuming no Yonko will take part in that is a back
fan fictions
please don't put yourself in Oda shoes and assume what you thinks is what Oda think
it's bold of any fan to do that
and one piece ain't a shitty story with a weak plot that any 20ish years old boys can see coming