So many times I am trying to make a smooth road that connects to a slope and since the angle and slope of roads are not always aligned it takes forever and causes a lot of frustrating going back over and over.
Also when trying to make square corners on interior or exterior walls it is almost impossible.
Option One - two new tools:
1. When holding down the control to flatten, add a mod to the tool that only adds and will not take away. Currently, if I have a wall and floor that I want to connect, if I flatten the floor to the edge of the wall it starts digging into the wall. An add dirt only would fix this. This would work for joining 2 walls a ceiling, etc...
2. When holding down the control to flatten, add a mod tool that only takes away and will not add. if i am trying to make outside corners or slopes connect this would prevent the edge from protruding over the existing slope or wall.
Option Two - one new tool
Make one tool that is a Flatten tool.
Standard mode would be a remove and no add flatten (this would flatten bumps and work as 2 above).
Alt mode would be an add and no remove flatten (this would remove holes or divots and act as 1 above).
And the control key would work as it does now.
I actually like the option 2 the more I think about it. With one tool on the gun (no switching) I can make new flat surfaces, and all the flat surfaces connect nicely.