starting with which modules you want and the modules you need to support them and leaving some space for expansion would probably be a good idea - a couple of mantises will work perfectly in that regard - start with one and add a minimum viable system and get to know that first - then proceed with the rest of the modules one or 2 at a time
I would suggest you add some more information - what sort of music you want to make with the modular and which modules are 'keepers' in this rack
then one or more of us can rip it apart and you'll end up in a better place - there are some obvious questions too - why do you need 2 trig31s? and 3 passive mults?
"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia
Utility modules are the dull polish that makes the shiny modules actually shine!!!
sound sources < sound modifiers < modulation sources < utilities