Good rack to start with I think. Are you planning to create specific types of music with this or mostly experiment? Does it fill a specific need soundwise that you are missing right now? (this is not to judge, do what you want, but purely to see what you want to achieve with this rack).
I have a feeling that some of these modules are selected because people refer to them as good starting points. This is definitely true, plaits is very versatile as well as maths. But considering your current rack size (again, depending if your're planning to expand it in the future) the modules are quite big. This enhances the comfort (especially when playing live) but can be a limiting factor in 84HP. These are just my thoughts, it's up to you to decide if you prefer comfort/playability/hands-on controls or you want more versatility.
Plaits seems to be a great choice because it offers a lot of different sounds. Mutable Instruments have made their modules open-source, meaning there a quite a few modules out there that behave like Plaits but have different (and often smaller) layout. There's quite some discussion on these forums if it's morally okay to buy clone modules vs. the original Mutable Instrument ones, I don't say one is better than the other BUT given that they are less HP, it might be worth to consider. Obviously less HP means smaller/cramped knobs, especially a smaller "Frequency" knob makes it harder to tune the module.
The Behringer filter has two independent filters and can be used as a stereo 3 channel mixer. This might be needed for what you want to accomplish, but given that you only have one main sound source I find 16HP for a mixer/dual filter quite a lot. Ask yourself if you need two separate filters AND two separate mixers? Maybe a stereo filter (which you can also use to filter two separate sound sources with the same filter) is smaller and better suited. Although the Behringer filter is nicely priced of course.
Music Thing Modular's Turing Machine is an amazing module, but if you want to randomly generate melodies with this, you probably want a quantizer (which "forces" the TM's voltage output to a musical scale, such as C minor). However you could also go for a micro Ornament & Crime, which are made by several manufacturers. Most of them come loaded with an alternate firmware called "Hemispheres", which has all kinds to CV utility modules build into it, of which you can load two separate on each half of the module. For example, you can have to ADSR envelopes on one half and a quantizer on the other half, or a slew limiter on one half and two LFO's on the other. It also has asort of Turing Machine built in, but with less hands-on controls.
I'm not familiar with the Noise Engineering Desmodus Versio, but it seems like a fully featured reverb module with a user-flashable DSP Platform. If you want to modulate your reverb to do all sorts of crazy stuff, this is definitely the module for you. If you want a reverb as something to make the overall sound more pleasant, this again is quite a big module for just that. Maybe you can look into the Disting MK4 or Disting EX, which have a lot of different functionalities including reverb, delay, but also filter, VCA, envelope etc. (sort of like the micro Ornament & Crime but with a less informative screen and more suited for audio processing). Also you can get a Mutable Instruments Clouds clone which has a custom firmware called "parasites", this also includes a reverb, delay, granular, and pitch shifter.
After typing this all out, it seems that I can summarize this into: you have a great start rack with lots of comfortable, hands-on control. There are quite a few modules that have more features in less HP, but this comes with the cost of smaller knobs and less hands-on control, aka less knobs that only do one thing or more menu-scrolling. Consider what is best suited for your needs. Also, if you want to use the Turing Machine to generate random melodies, consider a one-channel quantizer.
Cheers!