That is fascinating Swede. One night I tried to do that and didn't get too far before getting stuck. Are you using foundation to build the pillars?
Yeah, you first raise the ground and make a flat plateau and lay a foundation on that. Then you can erase the foundation bits so that it forms small pillars to this earth plateau (between each pillar you can have 4 empty squares. Then you sporadically lower the terrain here and there to approximately the same level and angle as the slope, then you use the smoothing tool to form everything to a nice slope.
I also discovered that it may be bright to keep a bit of the earth plateau left (you can see on my pictures that the foundation row furthest back still lies normally on ground) because then if you want to expand your platform you can use the equal-levelling tool to recreate the earth plateau with and then place out a new foundation where you see fit and start the process over again. If you destroy the whole earth plateau you can never place a new foundation on the exact right level as everything else again.
Also, a glitch may occur where some squares of flooring on your platform may be missing. In that case, use the cheat "constrainFloorElevation false" and you can place the floor tiles, but don't alter the earth level again without using the cheat "constrainFloorElevation true" first, because your platform may get destroyed otherwise.
Hope this makes sense!
@Storyteller: I think it looks good actually. You can easily see that you've toyed around with the house shape to make it less box-like, but it works well with the house overall. It gives it a bit of character if you know what I mean.