You can only raise/lower ground by +/- 8 meters from where it started. If raising ground with shift is too finicky for you there is another option. Raise ground, place stairs, then use the pick to lower the ground that has been raised above the stairs. The pick stops where the stairs start. This will give you a 26 degree slope instead of a gentle 5 degree slope but you can remove the stairs after and use the hoe to gentle the slope with a bit of practice..