Wow, thanks for sharing your process Brostavia!! I second the guy below, that is a lot of process, ha ha. It really helps beginning artists, seeing this kind of thing, because when all we see are finished works, we think that artists paint like that all the time and don't realize how much time and effort and study go into each good painting.
I have a question, do you usually start with several photos as a point of reference for some aspects of the design? I've seen a lot of artists do that in tutorials, ~abiogenesis recently did a tutorial for some website on how he painted a space fighter drone, and he first collected a bunch of photos of US and Soviet spacecraft, lasers, and so on, not to copy, but just as a starting point for the design. It makes a lot of sense, actually, great ideas don't come out of a vacuum and photos are a great way to get a visual understanding of how various real things work, and what design elements you want to include, and what to avoid.