is this for home/studio or performance?

if for home/studio I'd definitely consider 12u/104hp... and I'd fill the extra 104hp with utilities... this will exponentially increase patching possibilities... and I'd really look at 6u vertical-ish and 6u horizontal-ish - not perfctly - as you'll want a greater than 90 degree angle - so cables will fit...

tbh I'd also consider for live... as you'll be able to add matrix mixers and switches and other control modules... in the closest row...

"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