The only thing that needs to happen is making fast travel actual accelerated travel on-foot rather than a magical teleport.
Move a party icon on a map. No limits needed other than having been to the locations before. All appropriate limitations come naturally when you are really traveling from A to B, just faster. It's the most simple and elegant choice. I don't understand why Larian had to reinvent the wheel here and create a nonsensical magical teleportation rune network.
Random encounters would be a good way to breathe at least some life into already explored areas and make the world feel less scripted and controllable.
