As far as slamming your stem goes, if it works than do it. Fit is a relatively, fluid thing, and as a rider gets more cycling fit the rider will tend to get into a longer, lower position.

The opposite holds true at some point, when various aches and pains (typically from age or severe change in body/fitness) makes a higher, closer position more comfortable.

Slamming stems is just one part of the equation. It's part of the whole equation that includes leg length, steerer tube length, etc. On my bike a slammed stem (on a "short as possible" steerer tube) results in a position that's 3 cm (i.e. 30 mm) too high for me. The counter is that my legs are short so my saddle isn't jacked up to the sky. My saddle/bar difference is something like 8 cm, which is not that much.