Not undirected improvements. The first step is to fully specify what the behaviour should be, and if there’s agreement around that and a way to migrate without needing a deprecation then the deprecation could be removed. But I suspect it needs deprecation. (It certainly needs deprecation for a rename.)
Making a precise definition of what constitutes a “reserved” path, independent from any OS definitions (i.e. it should list any particular names, not say something like “and all the names forbidden by the OS”). And we would need it for both ntpath and posixpath.
Right now, I “own” the decision, but only because I’ve got the strongest opinion (and hopefully a little bit of respect) 
If there’s significant argument, then the process will become a PEP and the steering council will eventually own the decision. (Or maybe we take the two proposed plans to the SC and see if they’ll endorse one over the other, but most likely they’ll want two fleshed out plans i.e. two PEPs.)