www.atomicmods.com
Get the Li Ion AAs available from above, they weigh less than 4 AAAs and will push 7.2v for about 40min. They should improve your CG even more. Unless your doing some kind of friggin drawn out touring race, 40min should be plenty of time for what you have in mind.
Sounds like you're already on the lookout for CF parts, which would have been my next suggestion.
So have you tried any non-stock or mod'd stock 130 motors?