Route directory

It will be more user-friendly if there is a seperate directory for routes. users can then save their prepared routes in the directory for later use.

If I understand your post correctly, there aleady, effectively, is. You can open any stored gpx or kml file as a route. You can also put those files in subfolders--by trailhead or location--for example. These days, I've set Oruxmaps to automatically convert my tracks to gpx files. I rename some of them, put them in an appropriate directory, and now have a growing library, right on the phone.