So I've taken a closer look at the Effect Presets, and it only performs part of what I'm requesting/wondering about.
Basically, it appears that the Effect Presets currently acts as a clipboard to "paste" frequently-used effects. Once an effect is "pasted" in the sequence, it exists independent of the Effect Preset library.
However, my enhancement request is more along the line of pasting an effect as a "model" that references back to the library. And when the "model" in the library is changed, all the instances of this "model" in the sequence also updates accordingly.
So instead of it being a simple "paste from library," these effects would actually reference back to the original "template" in the library. And if the library "template" changes, all the effects in the sequence would also change accordingly.