it would be really nice if you could select a certain object, and only see connections that go to or from that object ... and be able to add objects to this set of connections, so you could trace the path without having a clogged cable workspace

A better way is to avoid getting cluttered cables in the first place, by using subpatches (objects [pd name-of-subpatch]). This allows you to break up a patch into smaller logical units, with connections between them, hiding the gory details. Sometimes it seems unavoidable having a mess of cables, especially if you're in the flow of patching, but it's harder to clean up later than make subpatches as you go along.