Your prompt reminded me about other features which would be useful in relation to routing and URL parameters.
I’ll often have a page showing results from a single query (ie a single action file), where the search parameters come from different sources. Eg there might be a keyword search form, one or more dropdown menus displaying categories and perhaps an advanced search. In the case of the menus, it would nice to be able to use routing - which in itself would be straightforward. However if the user then wanted to use a keyword search, I don’t think it’s possible to remove the path parameters left over from the categories - so it’s not possible to use routing at all in such pages (unless, hopefully, there’s some method I haven’t thought of).
Eg if a rewritten URL looked like /fashion/france/ and then, on the same page, a user wanted to use a keyword search resulting in a query string such as ?keywords=paris fashion 1923, I don’t think this is possible, because the rewritten URL will remain and the query will fail. As far as I know, query manager (in App Connect) can only add/remove name-value pairs.
There have been a couple of questions about removing all parameters from a query string - eg in this question from @transcoderm. Such a feature would be very useful - and solve this and one or two other problems.