I'm guessing its possible to resize the space occupied by the rail support to something like 2x2 (like the big electric pole)... but don't know how that would affect the extra directions introduced with this entity. But if it can be 2x2 regardless of position, then even better.

So, a option to reduce the size (even if doesn't look good or even passable) could help add value to the elevated rails (right now IMO, they aren't worth much)

I think the collision mask could be changed to any value (2x2 but also 0x0). It just won't match the graphics (i.e. would not collide even if you're building it on top of something else. Something like this.

What was the reason behind the need? I guess 4x4 is chonky, but it's as big as a roboport. So not too bad. For me the issue was the impossibility to build in between supports (like not even a smelting array), rather than fitting the support somewhere

Well, I guess the extended reach kinda serve the same purpose in a different way... but, with 2x2 we could probably build even more compact intersections.