to correct, candy ssj vegeth is a lot above buhan
fusions are simply too strong, no point ranting about it
gohan vs freezer 3° transformation is the biggest "inconsistence", from like 10-20k power with a single zenkai and rage boost he worried freezer that even with the 2° alone is above 1M.
even vegeta vs 1° trasformation is a bit insane, considering that until the previous zenkai he was under the ginyu squad