All they need to do is make more Airships and Summoing Stones for Raids/Dungeons. That's how WoW did it for a long time and honestly, it was way better than this system. They could also increase the speed of Mounts as atm they are agonisingly slow.
The Fast Travel in this game is just ridiculously over used and it does ruin the immersion in the world which really, is what you should play an MMO for.