Um...I've seen Vegeta do final flash 3 times in DBZ, and those are the only times he ever does them (not counting DBGT). Every time he did it it was yellow. He did it against Cell, against a Cell junior, and against Goku when Vegeta was Majin. And Kamehameha's are ALWAYS blue. And I don't know what your talking about, when Goku instant transmissions in front of Cell and fires kamehameha, it is white with a light light blue hue around it. I just now watched it from Kazaa to make sure. No matter when they are SSJ or not SSJ, the attack color is the attack color. Also, about big bang, I don't remember what color big bang is when he uses it against 19, but I do know that it is blue when he uses it against 18, and he was SSJ when he did that, so that dismisses your theory about color coordinated attacks right there.