The general concept is solid in #1. The stripes behind the fighter should be only white, blue, purple, brown and black. Also, the fighter is kicking which is not part of jiu jitzu. Jiu jitzu is grappling and submission wrestling and takedowns.
No worries. Jiu jitzu is a complex sport. I like the changes from #1 to #7. The belt progression looks good now, but think more pizazz! :-) and the Z can be red. I liked that about #1.Can you spread those colors around and incorporate them more into a general feel rather than a straight line progression? The fighter could have an opponent too. Maybe two fighters in motion...