Well, first up: if this is a rig that'll be spending a lot of its time processing external audio, I would reconsider that input stage in favor of getting something that has an envelope follower. That way, you can use dynamic levels from your incoming sounds as yet another modulation source, plus if the input also has a trigger/gate comparator with a settable threshold level on that incoming signal, that can have a number of uses for starting envelopes, sequencing, etc etc etc. While it's mono, still have a look at the venerable Doepfer A-119; Dieter got that thing right the first time, and that's why it's been around since around the beginnings of Eurorack.
Annoying that Mutable's chucking out some of their best and most prized module designs, yep...but like the Braids, look around for some of the open-source builds of the Clouds which have started popping up. What I've seen of these also give you some space-savings, so adding more functionality is possible if you go that route.
Also, this rack contains the typical 'if it's not sexy-looking, why do I need it?' issues...VCAs, mixers, panners, etc just aren't there. Again, if the task is processing, you definitely want things that can process dynamics in addition to timbre and so forth. Mults are missing, too; they're a must if you're going to branch process-control signals to several audio processing-type modules so that you can get some sort of parallel behavior going. Probably the best thing here is that, given this is MG, you don't have to drop the $$$ then have that 'oh, sh*t' moment when you realize you left things out that you needed. What I would suggest is that now that you have an initial idea of what might work for some of your tasks, toss this rack entirely while making note of these things (ie: print a spec sheet) then start over in a much bigger rack, perhaps twice this size or more. This tactic of 'build something bigger than _you think you need_' is important, because it lets you easily slip in all the 'unsexy' modules along with your previous specs...and then you start to realize that, hey presto, that _was_ what you needed!
Also, as processing goes, look for things that offer loads of modulation and strange routing possibilities. F'rinstance, have a look at the boring-appearing Doepfer A-106-1. Just looks like a filter, right? Ahhh...not so. There's a lot of weirdness there, such as an insert point into the resonance circuit, adjustments for tinkering with the paralleling of the two filters (yeaaaah!) there, a polarizing CV input. No, not a lot of flashy lights and zazzy graphics, but that module has lots of what I like to call 'abuse potential'. So it looks boring? That 'boredom' is only skin-deep. But this points out that stepping back and looking at other options, and by looking I mean not at what it looks like (the 'twistenknobs und blinkenlights' factor), but looking at the functionality indicated by the panel markings and control capabilities, is key to creating a system that clicks from the first power-up which'll avoid lots of module-swapping and the like. Might be a bit more tedious, but careful work where Eurorack's concerned yields definite results!
Lastly, module layout. Step back in time a bit, and look at some classic patchables that're still coveted to this day, and observe how their signal flows proceed across the patch panel. You tend to find designs which gather primary functions into specific areas...modulators in their area, oscillators all together, filters and then VCAs, etc. I still say the best example of how 'flow' works can be found on the ARP 2600; you always know where signals start and where they go to eventually, and when going outside the prepatched configuration and using the patchpoints, the resulting patches still tend to flow the way the prepatch does. Your above rack is going to be a pain in the ass to make decisions at a glance on, since patching is going to be all sorts of back-and-forth from and back to the audio interface, which will wind up with signals flowing both ways across the panel. Not fun!...and certainly not 'intuitive', which is what a good musical instrument should be.
So...step back, think bigger and more carefully. First attempts in an environment as possibility-rich as Eurorack NEVER come out right, but as I pointed out, careful work yields big gains and definite results. Good luck!
