Yeah. it's tricky and require very subtle curve node touch in openGL preview with a bit miss and hit. I always struggle to get a nice height profile out of SD tools . Only able to tweak it right with wacom pen by super small moves of those nodes. Contrary to what people typically believe I don't think SDesigner would do…
Just make a small bevels on tiles edges by curve node before slope blur of whatever you have used for edge erosion and they wouldn't be looking so harsh and vertical cliff like