Out of curiousity, what is your goal for this rack? You have a nice start to a synth here, I'd say maybe think about more lfos, attenuators, and vcas. But more specific recommendations really depend on what you're going for with this instrument.
-- HGsynth

In principle, my general aim is to really learn the possibilities from each individual module. Also, in general I am not going to use it for extremely strange sounds over which I have not fully control (up to random noise). So I prefer to have a rack without all those modules with a certain random characteristic... and maybe in the future, once I am under control of these guys, I will go into something more experimental.

More LFOs and VCAs sounds like a great advice. Thanks! But also I am going to use my Behringer 2600 with them, so in total there will be 6 possible LFOs + Maths.

I don't know if it is an answer. But I'm also yet figuring out what I can do with the modules I already know how they function individually, and what are other unknown possibilities out there.

And, of course, I have in mind to never use it in live.

Sam