@nickgreenberg - if you include sequencers and mixers as utilities, which I do in this case - then you are probably spot on with my guideline
re audio outputs - depending on where you are in the world they may be completely unnecessary - I live in Europe where we have balanced mains power - so I have never used one - straight out to external mixer/speakers/es8 - always try without first unless you know you need a balanced output (not all outputs are balanced!) - start with nothing, then try attenuators (or vcas) and then finally try an output module.. no point planning to buy something you may not need, unless you do!
"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