Not necessarily. Since I know what functionality you are after, my suggestion would be then to:
1. service/wrt rpc  in dashboard api as you suggested. 
2. we have webinos-utilities, content.js https://github.com/webinos/webinos-utilities/blob/master/lib/content.js.  IMO we should not have separate httpHandler for dashboard but rather consolidate at one place.
3. running with widget renderer or with browser, should be information available via PZP.
4. Providing lookup and registry is functionality this API provides, so should be part of an API. 

It is basically keeping your functionality but moving your manager component into multiple places. Instead of creating a new manager.