Calls 'em like I sees 'em.

Or if that's sarcasm I detect:

Stem height is going to be different for every single person and then that changes for each type of bike they own. There is a practical answer for everything and an aesthetics to everything. Find the place where both work for you, or decide how much of either you're willing to sacrifice.

It's like asking how much seat post I should run. If you have the right size frame, it's obvious.