+1 on putting the 500# on the rear from an armchair quarterback, I seem to remember CSG (or maybe Racecomp) claiming that 20-25% stiffer rear spring is going to give a balanced dynamic which leads me to assume that an even spring rate Front/Rear would result in a softer rear (read: more planted rear) than front inducing some understeer, I'm drawing a blank on the specific post but here's what some quick googling came up with.
Here is CSG's Tein kit:
http://www.ft86club.com/forums/showthread.php?t=82796
And here's a discussion on the idea but it didn't seem to get very far:
http://www.ft86club.com/forums/showthread.php?t=56678
Rear toe out will definitely help rotation, looks like it's a track only car so definitely try it. Zero toe in the rear was rather darty and unstable feeling on the freeway to me so I've got some toe-in for DD purposes, I may be reducing it in the future...