A lot of this speaks to what I was getting at with Morrowind. A limited fast travel system as well as a smartly designed map that utilized the limited space of the island efficiently.
Otherwise I think there's a difference between game design that improves something, making it easier to understand and use for the player and game design that removes those systems or automates them, taking them away from the player.
Because mobs in BG:3 don't respawn, nor does anything seem to change over time for us to witness, having fast travel points just cuts down on mindless backtracking sure, but it also stops those things from being a possibility. That and this funny thing that happened for me in Gyrmforge where using a fast travel point seems like the solution for traversing the map, bypassing a puzzle and a combat, probably with a split party (I'm not sure what 'legal' way of getting to the forge is). I also noticed that so many people weren't hitting the portal outside the druid grove that they made its discovery automatic. Having fast travel points that actually do away with map exploration doesn't strike me as good.
My vote would be for portal-to-portal travel only, that way people still can actually explore the map a little, even after they might already have 'cleared' the area.
Eventually you'll have made it from the beach on the Chionthar to a Temple of Shar deep in the primordial Underdark, and travelling between the two is as easy as clicking a button. I think that such a distance deserves a little more than that.
