...patch cables go from input to output hence an optimised system should ideally have the same number of these, no matter which modules are included...
-- Dan_ogq
I disagree. for me an optimized system is defined by other aspects than than the relation of I/O's
-  most important: can i achieve the audible results that i want?
-  is it ergonomic or is there room to optimise by rearranging some modules?
-  is it performable the way that i want?
-  is it easy to get every module perfectly in sync without struggling with missing clock ticks?
-  do i have enough headroom with my power supplies?
-  is my lightning ok regardless where my rack is located?
-  is there any audible result i want to achieve but not possible with modules i have?
-  is it easy for me to find/grab the right patch cables?
-  etc.
those are a few of my thoughts to optimize my personal rack...

