You've neglected to mention how some levers (shimano) pull more a few mm more cable than others (campy, SRAM), hence the need for slightly longer brake arms to keep maintain the same pull ratio... But hey, that's just maths, I guess brake "feel" is more tumblr or something...
My point was "feel" is subjective. There's a mathematical reason they produce two different arm lengths and that matching them up to the cable pull from your levers is good place to start, then decide if you want a little more grab/mush.
You've neglected to mention how some levers (shimano) pull more a few mm more cable than others (campy, SRAM), hence the need for slightly longer brake arms to keep maintain the same pull ratio... But hey, that's just maths, I guess brake "feel" is more tumblr or something...