What if caravans time were extended? So it's not fast travel, but it gives you time to rp on the journey instead of hold W. And possibly, more expensive ? I can see the Vistani wanting more money seeing how fat outlander purses can get.
I think if you have an option to take a 15 minute walk our a 15 minute caravan, it would be a decent alternative to running the entire trip like an Olympian. Also, if it were say, 500 gold, it would divide the rich and poor creating resentment rp opportunities.
Other things are the cost of the Vistani elixir. 5 coins is too little. Also, could it be required for both directions? It's always seemed like it should.
During non winter months, you have the ferry, which is pretty op considering you can get from the Fisher lodge to midway in an instant. It cuts travel time down significantly, almost in an unbalanced way. I would be willing to do more caravans and no ferry at all, if I an honest. That includes to krezk, the lodge, and other places the Vistani might take you on a slow, bumpy wagon instead of a time bending instant ship.