I label them base on a word that is reasonably describe them.
Buggy has his pipedream ambition that himself is incapable to achieve. He doesn't have a single road poneglyph and he wanted to go for the One Piece.
Blackbeard is bad because his wanted to destroy everything and rule the world with tyranny.
Luffy is good because he is savior of multiple kingdoms.
Shanks warned Whitebeard not to pursuit Blackbeard because it will led to something catastrophic. Then he stopped the war so suffering will not go further. He is the symbolism of a wise king.
If we could use one of the word to give to one character on each side.
Left Side
Koby stopped Akainu from attacking fleeing Whitebeard pirates and it was then supported by Shanks helping him, saying he did the right thing. He also join Sword as a rogue unit in support for true justice.
Kuzan is a fool because in order to fulfil his agenda so he joins Blackbeard (evil).
Right Side
Imu is Evil because we know he destroyed Lulusia.
Dragon is wise because he left the Marine to pursue true justice.
Akainu is a fool because he perceives all orders from Celestial Dragon are justice.
It just left the Spanks silhouette for the good.
Spanks probably is the man marked by flame, Shanks twins, traitor of god's knight. In this Vegapunk sentence about One Piece, he might be the protector of last road poneglyph because he is only person that is holding a weapon up like a guarding position.
I think getting the last poneglyph will not be easier than the one from Wano. There will be a huge fight with or without the clash with anyone in this page.