Sounds agreeable enough; a lot of the anti-flight crowd seems to have a chip regarding its effect on world PvP, which generally doesn't really affect PvE/RP-PvE servers (I'm assuming you also want them disabled on RP-PvP servers) since world PvP takes two to tango on PvE/RP-PvE.
It would require all quest hubs/daily areas (like the virmen and hozen villages/camps/what-have-you north and northwest of the Heartlands in Valley of the Four Winds) to be redesigned to be accessible via ground mount or through a special dialogue with local flight master, both in current content, previous content like the Tempest Keep 5-mans and raids, and in future expansions (which, while not really problematic, would put a little more on the world design and art teams' plates).