chopin2256 - 10:23 pm on Jan 15, 2012 (gmt 0)
Thanks for the assistance, I've simplified my rules using your advice. I couldn't get [^/_-] to work, but (.*) does work fine. I don't notice any lag on my site due to this, possibly because the strings I am substituting are short anyway. For example, the distance from (.*) to .-c1 will be no more than 10-15 characters per substitution.
I've come to realize that there is most likely no way for me to get around the dozens of combination rewrite rules due to the nature of the faceted browse. I suppose this is the tradeoff of trying to write a user friendly dynamic multi-faceted directory, vs leaving the url structure alone and messy, but without any problems.