If not that, what would you offer as a compromise that might entice the Chantry to the negotiating table?
Your suggestions are based on the implicit assumption that the Chantry's ideology is rightfully dominant. That I contest. To agree to the Dalish mages having to go to the Circle, for instance, that's like - to use a current example - to give in to Turkey's demand to extradite supposed members of the Gülen movement on their say-so, with no evidence that they've done anything wrong. It would go completely against fundamental aspects of the Dalish culture.
Any compromise that deserves the name has to treat the two cultures as equally valid, to start with (not that I think either one is particularly worth defending, but that's a different story). To agree to stop killing or imprisoning each other would be a good first step, along with visiting rights into the other's territory (not by armies, of course) in order to get to know each other better. Cultural contact, that would be the way to co-existence. The implicit assumption of superiority has to stop, on *both* sides.
Agreeing to cultural contact would be a big step for the Dalish given their present stance, and especially since they're the less powerful culture. The other side has to recognize that. What comes of that, who knows? Maybe the Dalish will have to stay in remote regions in the end, maybe not, but I see no justification for a demand to submit to Chantry rules regarding mages, except perhaps for the surplus mages who would otherwise be cast out. As for their system of rulership, it isn't any worse than any other system on Thedas. That you change how you select your rulers as demanded by someone else is actually a most significant indication of submission. It's about the last thing any culture would agree to.



