It took me a while but I finally found a solution on how to group scenes togheter. I was wondering how I could transition smoothly between different scenes without having a loadingscreen between each scene.
Let's say for example you have a main world with a couple of dungeons or some NPC houses you could enter. Yes there are different ways to approach this but bear with me for a moment.
What I did was; I created some kind of " Level Controller " that will accept different ScriptableObjects called a " Level ". On play the " Level Controller " will load an initial level that has been specied by the developer and it will load all the sub-levels of this root level. When everything is loaded it will deactivate all the "un-unsed" levels. Whenever we want to traverse inside another scene we just need to activate all the rootobjects of a scene ( which already availble from inside the Scene struct itself ) and deactivate all the objects inside the root objects inside the scene we are comming from.
I tested my results and switching between different scenes has now become much faster.