This would be very nice since the current terrain block max is 2048m, My hope is that eventually you could just use a ground plane which would mean you could make a map as big as you wanted.
very unique and creative that I'm sure the devs would have never thought of... if they could do it easily then they would.
You can change the scale to whatever you want. 2048 is the maximum height map resolution (although I think 4096 works too)
4096 maps are the limit last time I checked. They can 'stretch' much bigger if you set the meters per pixel to 2 or more. Your terrain resolution or 'detail' will suffer heavily beyond 2 meters per pixel. This can be limited fairly well with a very detailed and very thought out heightmap specifically designed to take the extra meters per pixel into account.
I know you can change square size but like aboroath said "Your terrain resolution or 'detail' will suffer heavily beyond 2 meters per pixel." Which is a big issue for me. I am also not sure how you can make a flat height map bigger the 2048m x 2048m
I dare say map size is limited due to floating point precision errors, if this is the case they can either have bigger maps or multi-player but not both due to MP needing a static 0 coordinates while bigger maps would require mobile 0 coordinates.