There are more than just the imagespace and weather that adjust the exterior lighting for instance, but those are the ones that creates the base look. Each weather have normally 4 different imagespaces assigned to it, 1 for each time period which are Day, Sunset, Night and Sunrise.
Then there are these things that alter lighting as well;
Lighting Templates - You might call it the "interior weather" control as it has similar settings that can be found in the weather dialog window. Fog control, ambient and directional lighting and so on.
Imagespace Modifiers - Similar to imagespace but are used for special lighting conditions such as the Night Eye effect, the blur screen when you get hit and similar occasions where lighting changes for a few seconds by some trigger for instance using the Night Eye effect.
In simplest terms weathers assign specific RGB color values to different objects while imagespaces controls overall scene color and does not alter any specific object but instead adjust them all equally.
Who is this teofis and what has he created that will allow you to disable Skyrim processing? Is it similar to what ENB does with the APPLYGAMECOLORCORRECTION or something more along the lines of the Imaginator by using Skyrim script language to be able to adjust certain imagespace settings??
The weathers don't have any HDR effects there are only RGB and alpha color values. Imagespace however have something called "White" command which let's you adjust the max RGB value that can be used, similar to EToneMappingOversaturation visually at least.
I have some experience with the Creation Kit/CK but I do not know of this CE editor you are referring to

They still need a lot of work before I release them and I also need to find the best place to put them in the sky.