I'm trying to figure out how to handle Worldwalking and vampires.

First, there is the question of strength of the barrier between the real world and the Never Never. YS283 makes it clear that the barrier is diminished if the character has an affinity for it. I'm not sure if this should be a straight "Yeah, it is lower" or if it should be an invocation of the high concept aspect.

Second, the opening itself. Should vampires (in general since there can always be exceptions) have a way to open a way to the Never Never? My gut feeling is that they should have some means to actually open it (such as one of the forms of spell casting), which is just aided by their vampiric nature.

I don't have a lot of experience running FATE, so I'm looking for some recommendations on getting the balance right. I don't really want to drop too much power in the hands of players without them paying the price (aside from the inevitable "there's something nasty on the other side") for it.

Anybody got an opinion that they'd care to share?

Thanks.