Interesting stuff about the slick strips. Please make sure you post back when you have tried the graphite or chosen some other solution. I've always used UHMDPE for slides but was going to try slick strips next time. They look like a nice simple solution.
I've been out of town for a few weeks but just got home and had some time to mess with this last night. I drilled 3 holes for air on the rear of the main boxed frame to allow air to move when sliding the drawers in and out. I think if I was going to do this again I would not make the sides of the drawers as tall. Mine were as high as they can be but there's really no for them to be that tall and if they were shorter I think it would allow air to flow better.
I used almost half a can of the 3m dry graphite spray and hosed everything down pretty good last night inside the frame. This plus the air holes made a huge difference. Things slide nice and smooth now. There's some initial sticky'ness to get the drawers moving but once they are moving they slide pretty freely.