Thanks for the detailed explanations, really appreciate it. Following both your advice I switched the mutamix with the panmix. Can't wait to get started with it.
As I said in my first post, this thing is gonna be built at a slow rate, mainly because I wan't to get to know my modules first before buying some new ones. Any suggestions on which ones to buy first? Some starting combinations that might provide some great fun in the beginning?

The rack now looks like this
ModularGrid Rack