To prove my point you reduce me to stateing power levels...
Volume 12
Cyborg Freeza - 6,500,000
King Cold - 4,800,000
Trunks - 5 (Supressed)
Super Trunks - 11,500,000
Super Goku - 13,500,000
Volume 13
Yamcha - 58,000
Nineteen - 4,000,000
Super Goku - 7,500,000
Nineteen - 7,000,000 (Post-Kamehameha)
Super Goku - 6,000,000
Super Vegeta - 16,500,000
Nineteen - 8,500,000
Now that's made my point...
I'll explane (As you seem confused) why Goku is stronger...
Vegeta's base PL was always and If I'm not mistaken always is stronger than Goku's.
Goku however had Kaoken (and super Kaoken) on his side allowing him to push his Pl Over Vegeta's.
((Stick with me I've got a aditional point to this))
After the training in the room of spirit and time or whatever you know it by , Goku's SSJ pl multiplyer went up above Vegeta's...
Meaning If Vegeta and Goku started with the same PL
((Say 100 as its a nice easy to calculate number))
Vegeta would be at say 235 PL at super sayain.
But Goku would be at 375 PL super sayain...
Interestingly enough this begs the question could Vegeta be given more starting power level than Goku and leave out the Majin Transformation.
Maby even give Goku a higher SSJ power boost and less of a SSJ2 power boost (So Die Hard fans can pretend or not pretend if they so choose) that Vegeta's SSJ2 transformation includes the Majin Powerup... Like the ESF team origonally intended (Not the Multiplyer idea - the fact that SSJ2 and Majin would be 1 single same classification of transformation)
That way It'd add some more (all be it lop sided) strategy to useing SSJ and SSJ2
For Example.
Base PL Vegeta > Goku
SSJ PL Vegeta < Goku
((Maby Even to balance the SSJ3 part)) USSJ Vegeta > SSJ Goku
((SSJ2 Replaces USSJ once reached))
SSJ2 Vegeta = Goku (ish)
SSJ2 Vegeta > SSJ3 Goku
