gorosei are underlings
kizaru fujiroa and GB are also underlings
and mihawk isnt a big player in regards to the one piece either, when buggy mentioned plans to go after it , seems like a battle he wants no part of . or you could see it as buggy representing cross guild.
kidd and law may help luffy but doubtful they will be major players.
I agree with most of what you said, the characters I mentioned are still important to the story but not during the battle for the One Piece.
But yeah the Gorosei are basically Imu's underlings.
Fujitora and Green Bull are Akainu's underlings.
Kizaru will be taken out in this arc or play the same role as Fujitora and Green Bull.
Mihawk doesn't care about the One Piece and his focus is mainly centered around Zoro.
And Kid and Law are both out of the race for the One Piece.
I mentioned this before but I think it's dumb that some people are using that panel with those characters to downplay characters like Mihawk and the Gorosei just because they aren't shown.