ABANDONED HIDEOUT

[Trinity]

Hey folks!
First time posting for me so I'm just gonna say sorry for any issues with the posts, I haven't been very into forums. 
I actually started with landscape light and color studies yesterday in anticipation of joining the Abandoned Hideout:


Now that I look at them they look very rough, but I'm aiming to get more patient as I go along.
I'm also working on some sci-fi stuff at the moment. I've been doing fantasy for a long time so I decided to switch it around. It's gonna be some retro sci-fi set in the 70's. Atleast that's what I hope. I wanna learn to use a certain design elements to make imaginary things look as though they fit in in that era. This picture however is not meant to be influenced by the 70's. This is a building or vessel of some sort that has been left behind by whatever beings, that contains the technology used to create the 70's sci-fi stuff. I'm not sure if this representation is technically sound enough to have it's design commented, but if it does I would really appreciate some design feedback!