A>Third Raikage>Bee>Darui>Sasuke>Kakashi
I think it would actually go like this
Third Raikage>A>Darui>Bee>Sasuke>Kakashi
The Third Raikage is basicly A and Darui combine, he has A's Armor and Techniques, plus he can utilize Black Lightning. I was hoping to see the master of black lightning utilize it in the war, but i guess kishi cut it short :[ no black lightning armor or blacklightning vs Amateratsu (black flames).
A is second for obvious reasons, he can do more than Darui even though Darui has Black Lightning.
Darui is third because he uses more lightning attacks than Bee they would be a close draw if its a all out lightning battle only.
Bee is third, he doesn't show much of his lightning tech but it is probably because he has the Hachibi, he is still over Sasuke tho, coming from the land of Lightning i'm sure he has other techniques within his arsenal.
Sasuke is behind Bee but over Kakashi. Obviously he has surpassed Kakashi in lightning techniques, being able manipulate it to a higher level. He is probably the best Raiton user outside of the Lightning crew.
Kakashi was the first shown to use any lightning technique but not all his moves relies on it. He is behind the rest but is still up there with them being the second best and could be debate to be better than Sasuke also being his teacher most of sasukes lightning attacks exist because of kakashi.