In a REST API, you shouldn't be overly concerned by predictable URI's. The very suggestion of URI predictability alludes to a misunderstanding of RESTful architecture. It assumes that a client should be constructing URIs themselves, which they really shouldn't have to.
However, I assume that you are not creating a true REST API, but a 'REST inspired' API (such as the Google Drive one). In these cases the rule of thumb is 'path params = resource identification' and 'query params = resource sorting'. So, the question becomes, can you uniquely identify your resource WITHOUT status / region? If yes, then perhaps its a query param. If no, then its a path param.
HTH.