I have the same problem with my Dark Eldar army.
I've found that the longer you leave the model in green stuff, the easier it is to strip. So I would just fill a big ole bucket with 2 whole gallons of green stuff, submerge as many models as you can, and forget about it in the basement for a month or so.
I also got an ultrasonic jewelry cleaner to HOPEFULLY eliminate that "scrubbing" step as much as possible. You can get a cheap one for about $25 on Amazon. In theory I should be able to just put the models in the jewelry cleaner, run it a few times, and they'll come out spotless... i'll let you know how it works.