Raise and Lower Ground in Create-A-Park
Raising and lowering the ground in segmented blocks (think Minecraft) was a fundamental part of the Create-A-Park editor from THPS4-THAW. It was sorely omitted and missing in both Proving Ground and THPS5. This feature of the Create-A-Park editor is truly a fundamental part of being able to make great parks. Without it users are only able to make flat, boring, and uninteresting creations with no elevation or depth to them.
Does this suggestion exist in THPS1/THPS2?
If no: please provide reasoning on why it should exist in the THPS 1+2 game.
Partially. You could place risers on the ground in THPS2, but only to a certain height. And then lowering could be done for some pieces but would fill back in when the piece was removed.