Not too bad Brad. I will give my 2˘ though...
1. Make the light source in the cabin more dramatic. Have it blur a bit on the outer cabin wall and cast a window of light (faded or softer than the window light) on the ground.
2. Make the cabin lines a bit thicker and soften your background shades. Foreground is by nature darker and more detailed and the tones get softer and more hazy as they fade back. Think about what the central focus is and put all your dramatic lights and darks there (cabin). Then balance the others around those shades and tints. The cabin is not pushed out enough and it sort of blends with the other shades around it. Make everything else a vehicle to guide the eye to the cabin. The dramatic light works, but you have elements you can tinker with to radiate inward and guide the eye there.
3. Your sky is great, but it consumes a lot of the picture space and composition. Always think about what you want to be the central focus and make it a picture of that rather than the supporting elements.
4. Acrylic for the sky is an okay idea, but I do recommend (and abuse) correction fluid pens. I like the Bic Wite Out pas the best. You have to squeeze and shake, but they give the most consistent flow. You press the tip down and squeeze a bit and then dot where you want or spread the pool released around. I stopped using Pro Wite because I would have to do three coats before I felt satisfied with the coverage. Ayway, they will help with any corrections and to dot your sky. The other thing you might try is a liquid acrylic and mask off the areas you do not want stars. Then use a toothbrush and flick your galaxies on there. Any you don't want can be easilly blacked out.
While I question some of your materials choices, I do think it is a nice thing and can get even better. The experimentation is important. Try everything you can to get a taste or feel for the different materials, techniques and styles you can use.
