I disagree, I think that they should move to a caravan (etc) based travel, where you have to pay for fast travel and you can only travel between settlements or whwre ever the caravan goes. Best possible option would be a wolrdmap travel like in the previous games with the nodes being about 1.5-2 times the size of point lookout. And if the world is build that way they can even include cars without turning the game into a GTA mess.
The Fallout 3/Oblivion fast travel doesn't do justification to the setting (both TES and FO). It's a simple, immersion breaking and cheap alternative to somehting that actually makes the player involved in the situation and should not be continued.
There simply
has to be a happy medium to be found in this issue. Because I seriously cannot see myself playing a game where I'm forced to trudge around on foot to the nearest "warp point," just to be able to quickly get to where I was headed in the first place. (ie, if I want to get from point A to point B, I really don't want to instead be forced to go from A to C, which warps me to D, just so that I can walk all the rest of the way to B.) A "caravan-only" method does just that, however. To me, that adds extra time that I'd rather be spending on those elements of the game that are actually enjoyable. I consider any time a game becomes tedious and less-than-fun, to be a flaw in it's design (the whole point is be entertained, after all...)
And, of course, many players feel that not having the fast travel system fully integrated into the game world, to be "immsersion-breaking."
Let's break this down a bit, then. No matter what system you use to quickly get from one already-explored area to another (because I don't think there's much of an issue, here, with the player needing to have actually visited a location before they're able to fast-travel there,) all you're really doing is entering a load screen, and finding yourself at your destination. If we take a "caravan" system (and by "caravan" I mean any sort of warp point - trains, buses, taxis, caravans, etc,) then you walk up to the caravan, select where you want to go on some sort of World Map, and then you hit a load screen. In Fallout 3-style fast-travelling, you open up a World Map, select where you're going, and hit a load screen.
Really, the only difference then - in gameplay terms - is that in method you have to go to a fixed point before the load screen (and presumably can only travel to other fixed points,) and in the other you have to be outside and not in combat (but can otherwise go to pretty much wherever you want - so long as you've already been there.) Now, we can assume that the primary form of transportation in the Wastes is going to be your own two feet - there's not likely to be any place in Fallout 4 that you can't get there by simply walking your character physically to that location. So personally, I'd find that it would break my "immersion" just as much to have to deal with a game mechanic that forced me to use vehicle transportation (ie, caravans and such) just to quickly get me to a place that I could just as easily walk.
The only difference we're talking about here is in-game time spent travelling, then. Anywhere that a caravan would be able to fast-travel me to is a place that I should be able to fast-walk to just as easily. That just makes sense. And the whole point of having any method of "instantly" getting from place to place is to make things easier and not bog the player down. In other words - caravan travel and "fast-walking" (ie, Fallout 3 where the game compresses time and assumes that your character has walked that intervening distance - calculating how much time has passed during this action,) are the same thing. They only differ in presentation.
So, to avoid "immersion-breaking," I think it might be fair to venture a guess that the only thing lacking is presentation. If there was some way for the game to present the fact that your character had just taken a long trek on foot across the wasteland; that time passed, and nothing of note happened along the way - then I don't think it would be as much of a problem to people. We could still have caravan modes of travel, as well. There could be nice bonuses to that - like different random (or decreased chances of) encounters, more assistance for dealing with those encounters; or any number of things. There could be a clear advantage to taking a caravan to the next town or waypoint. But there also needs to be a viable option for (in my case) the other 90% of the game, where the place you're actually headed is nowhere near where one of these "waypoints" would feasably be located in the first place.
So, instead of trying to choose one at the expense of the other - I think it might be a better solution to try and come up with a system wherein both methods of fast travel could co-exist with each other - where the inclusion of both actually complement each other and serve to make a better game for everyone.
That's my idea, at least...