Cloggerdude vs. Jackal
This battle is pretty impressive. Both are great at RBY. I'm just going to go with the person I'm more familiar with here though. I've heard good things about Clogger, but I think Jackal can pull this one off.
Gomez vs. Winner of shini latios/Eagle
I'm highlighting myself for the sole purpose of boosting my confidence which is something I often do to prepare myself for a tough battle.
Lesm46 vs. JMC
Woah, this one's really good. Lesm's got the luck and all going for him, but I'm sure that JMC has a bit more UU experience, and he can pull it off with a tad of luck to counteract Lesm's :).
ShinySandslash vs. Fish
I don't think I've ever seen ShinySandslash battle RBY. However, I do know that Fish will feel right at home in RBY.