It's not a bad idea to be honest, but in general I do not even approve of it.
I can understand why it would be nice for some if you'd for example leave on the west side of the heightmap and appear on the right one, but there's many things that would be difficult with making this, and if I'm going to stay realistic I do not think this is something that will ever happen. Not all maps will look like Fluorite or bonfire so the heightmaps wouldn't match, nor am I sure how a characters position would change and update as they run into this loop and end up on the other side of the map, more issues that would need to be solved really.
But in general I like the invisible walls, but it depends how they are actually made. If map is made with areas that actually look like there's something beneath the barrier and not like something like South Pole works, then I get a bigger feeling of it being endless and a bigger world you are in even though the map itself is rather small. To be honest I don't get why people are so annoyed by these walls, they exist in lots of other games out there just that they are done in another manner such as having fences, rock walls, buildings etc, and FH isn't the ordinary MMO with extremely large worlds that load as you pass over it so we are limited.
I kinda like boundaries to be honest since it lets you create distant landscapes and make a map/world appear bigger than it actually is.
