I guess the fast travel VS no fast travel discussion is totally irrelevant. Fast travel is necessary with such maps.
On the other hand, from what I read it looks like many people don't like the runes and for more than justified reasons.
Giving us the feeling we're walking instead of using WTF runes that doesn't exists in the Forgotten Realms is easy and there are more than one solution.
About the "rest" system, it's definitely a problem at the moment but it probably require way more attention than what this topic is about.
there may be a reason why those runes exist.
A reason why we're the only one able to travel through those runes ?
Let me attempt something : the tadpole ?