I created a tutorial on how to us multiple instances of ÜberMod in series and parallel to create complex reverbs:
Building complex reverbs using ValhallaÜberMod
I was playing around with this the other day, and was honestly surprised at the results. ÜberMod was designed to do a lot of things, but "standard" reverbs weren't the primary goal. It turns out that ÜberMod can generate all of the components of a "complicated" reverb (early reflections, input diffusion, late reverb), and does a pretty good job at all of these tasks.