84hp - doepfer lc9 cannot be beaten economically (cost/ total hp) - but may be a bit under powered if a lot of high power modules - analog modules are fine - some digital ones are horrific...
104hp - mantis... exceptional case - a bit low on -ve rail for my purposes (video) but great none the less!! I have one of these and use it for video or as a portable audio case - fantastic and rock solid - quiet as you could want up to video rates (no dirt in video) so also perfect for audio
or build your own - if you have basic wood working skills - ie you can use a saw and a drill (I could even 35 years + after doing any)
and a screwdriver - then you will save yourself a lot of cash...
as with mixer channels, audio interface channels and vcas - always, always go bigger than you think you'll need... because you will, sooner or later...
exception (there are always exceptions) is if you have a massive case already and want a case specifically to concentrate on a new module or as a satellite - ie control, sequencing, effects... as for portable pull out cases - that's what my mantis is for... portable by anyone except small children, the infirm or exceptionally elderly - mine's been on many - otherwise beauty cases are for people who need to fit their modular synth in their handbags...
"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