This would perhaps be more appropriately filed as a feature request, but I've noticed two differences between the 'outages' and 'resources' API endpoints:

/resources/fornode/{nodeCriteria}
vs.
/outages/forNode/{nodeId}
 
The most trivial problem is that "forNode" (or "fornode") is spelled differently, and the API is case-sensitive:
 

This constantly trips me up while testing or while writing new integrations, so it would probably be beneficial to fix the casing for one of the endpoints, while still allowing the original spelling to avoid breaking current implementations.

The other discrepancy is that outages only accepts 'nodeId' as the identifier. All the external systems I use to access the API only deals with the 'foreign-source:foreign-ID' tuplet, which means an extra request to the 'nodes'-API before it's possible to fetch the outages for a node: