I don't think anyone has tried to build something like this yet for Diplicity. Games for complex variants often happen via dedicated Discord servers (or whatever the top level channel grouping is called).
Integrating with the existing server would be great - it's been designed to support different clients. However I'm not sure what the aim would be with this client. Maybe you could list the channels used per game, and any additional channels needed to join games and change settings?
Previously I made a Discord bot to report when phases had completed, but I never managed to include a map with it. This used a third-party site (I think I used "if this then that") to convert RSS to webhook calls.