Here's the issue (or choice) as I see it:
1. Make Zones (Optionally) able to have Conditions, similar to the conditions you can add to rules in the Options -> Video -> Video Mode: Custom configuration system.
2. Create a new system of DSP Profiles, which can auto-load based on similar conditions.
The downside to using Zones is that Zones can also be used to play things simultaneously via different outputs (or the same output with different Detached Displays in the case of Video), and having an auto-loading Zone would conflict with this use-case (where you need to be able to manually switch to a zone and play something, and it stays there and has it's own Playing Now). That is, after all, the primary use-case for Zones. That's bad, I agree. If you wanted to have both, you'd have to carefully craft your Zones, and it would get confusing with duplicates of everything. You'd also need some way to reorder zones or prevent the user from adding the same condition to two or more zones.
The upside is that you combine multiple related functions into one unified interface. You can get rid of those other settings, and unite it all under the Zones configuration. We could have just one place to go to configure all of our "output" (DSP included).
The downside of option 2 is that it begins to create an array of interacting separate semi-automated fidgety-widgets that seem to threaten to become sentient and try to take over the world. Right now, we already have an auto-loading by conditional configuration system, in the Video Mode Custom settings. So you'd have these rules over here (which can affect Audio), which is this rules system with conditionals, and then you'd have this auto-loading profiles system over here for the DSP, which may-or-may not interact with your settings in the Video section... And then on top of that you have Zones, so you can have multiple different sets of these crazy setups. And on and on and on, and then before you know it we have someone posting on Interact with so many weird zones and profiles and video custom loading conditionals that no one can ever diagnose what the heck is going wrong with their system.
And you just rebuilt the horrorshow previously known as Windows Merit based DirectShow playback.
The upside is that it does not interfere with Zones in any way, and you can use Zones to have "swichable" sets-of-sets of complex rules. That seems pretty advanced to me (and probably making a lot of trouble for yourself down the road), but it would be more powerful, and perhaps less limiting/awkward.
So, I don't know. Either one would work. They both have their upsides and downsides.
I too would be happier if I could center-balance Movies more, while keeping Music with JRSS as-is, so something towards this goal would be appreciated.