Mist travel is not something to be taken lightly, which is why, in our design plan, it's reserved more or less to higher levels. Roughly, our design plan is like this:
At a low level, you are trapped in Vallaki, Barovia..it's a backwater town, people speak a strange language, you feel alone and helpless. As you progress, you slowly but surely venture away from this town to explore Barovia (hence why higher level dungeons are spread further and further away from Vallaki). Eventually, you reach a point where you start venturing with these Vistani, the ones that were so mysterious at first; and you discover new lands. Your scope starts to broaden, you are able to explore more realms and worlds.
That's more or less our design philosophy. You may disagree with it, and I'm sure quite a few will, but it's what we base our design decisions on. Level range and everything is aimed at achieving that goal. Now, if at level 2, straight out of the Mists, you'd just be able to talk to a random Vistani and hop around the Mists carelessly, it wouldn't have the same feeling.