Setting for Raw file

Hey,
when u coose between create terrain and rawfile and u take terrain, we are able to set many settings. But if we choose raw file we cant change any settings.
pls add the possibilty to set settings by creating raw files.
this gave aus the chance to make a heightmap with better qualiy without running out of space error.
after generating this raw file, we can  import into Unity and use it for a terrain.
what u get on this way? ->
1. better heightmap quality
2. the posibilty to use inbuild unity terrain tools on a big map (witch isnt spread)/ if u create a very big map with this programm u have to set the count of terrains to a higher value. so if u want to change something u only able to change a small field of the complete terrain and u will get unintentional borders between the terrains. And yes i know that i can export the complete raw heightmap after creating a normal terrain, but this will bring some kind of problems at using on my way.

Thank you