Hello! Welcome to the internet :)
Other than trial and error and just seeing what feels right to you, I've seen a lot of trends on racks keeping the sequencing things, the controller things, and the stuff you tweak the most the "furthest down the rack" usually closer to you if you've got a two tiered rack or something. I'd try to position things to minimize patch cable distance and to group common type modules together.
Aesthetically, I moved all the Moogs ontop of each other so that it looks cool and all the patchbays line up. If you have a 4 row case, I'd move the neutron over ontop or below the moog stack to line up all the patch bays. That will probably result in the least number of headaches. Moved the mult to the middle area to jump modulation sources from one side of the rack to the other. Sequencer, mixer, and joystick towards the bottom, they've got a lot of their outputs on the top of the module as well so that when fully patched you can access the knobs easy. Then I fit in everything else in the space provided. Put the model D in the top right because it has the last number of patch points. Circling the red neutron looks cool to me also with it being center.
Cheers!
Edit: if you put the DFAM on the bottom, that's mostly a row of percussion, the middle row Mother32 that's like two subtractive synths next to each other, then the top row is like, other stuff, seems to click in my head. The midi jack on the right of the mother also all the way to the left seems to be a good spot for it. There's a DFAM to midi module someone made recently that you might be interested in if you'd like to connect your DFAM to a DAW or something. https://www.modulargrid.net/e/sonoclast-mafd-2hp-midi-adapter-for-dfam