So i was unfortunate enough to have my base terrain resetted, this is most likely due to me paying a trip visit to a very populated system full of other people's bases and upon my return home my home floor was covered in dirt and grass.

Id really love if they added the option to select for instance an object or building part, and have the additional option to flatten the terrain surrounding it, like it does when you place the object, would a extremely useful addition to the building system.

I think that a flattening terrain tool is in very high-demand by players, especially novice players who want to start base-building. Hello Games seems to go the other way round: They make base-building even more difficult and problem-proned by allowing you to build everywhere without the necessary tools for pending terrain, making the players go frustrated in the experience.
Good tools would be for example foundations that you can elevate over the terrain and that will snap together with other compounds you add above. This is not true currently, there are foundations but they will get buried by the terrain generation. And terrain generation will always win against base building objects, the generation doesn't consider objects.

There is a very simple solution for Hello Games for the novice builders: It's to add a very big flat terrain to find by the signal booster with a base computer in the middle waiting for you to start building. The funny thing is: Such a POI location already exists in the game, although very rare and probably on lush planets with grass only. If these locations could be found via the Signal Booster or the Cartographer, this would be the perfect solution for who wants to start building without annoying constraints.

It's astonishing how Hello Games misses easy opportunities to include better game features that don't take much time to implement. I have the strong feeling that the coders at HG should stop working now and then, and go play their own game more often, just for the reason not to lose the big picture...