Zones are the best solution offered by Media Center for the issue of wanting two different output configurations playing to the same device.
There is an option to save DSP Presets at the bottom-right of the DSP Studio window, and you can apply them to files via tags.
The problem is that it saves the state of all DSPs instead of select DSPs. Presets are applied by tagging files instead of being rule-based, and changes made to the state of DSP by presets are permanent rather than temporary.
Hmm, not sure how I overlooked that for so long. I know I've noticed you could save/load presets but never knew you could assign them by the "DSP" tag. There is nothing that alludes to this fact. Clicking the HELP in DSP takes you to the wiki that makes no mention of this at all.
I think this is an example of what some people talk about when they say MC needs a UI change/easier to use. Features remain hidden to a lot of people, even some like this that seem like they should be more obvious. Honestly I have no problems using MC in its current state but understand what they mean. This as an example. How is a new user ever suppose to know they can assign DSP to tags?
I agree that rules based way of applying a DSP is a better way to go. Almost everything else in MC is rules based like creating smartlists, views and even auto zone switching. Why not DSP presets? Just seems out of place with the way everything else in MC is done.