Manga Colouring: Background

I kind of struggle to paint this piece as I am weak in painting backgrounds.
I welcome all constructive criticisms! As usual, lecturer guided me throughout the process.

Completed piece of the practice.

First step is to apply gradient with the right colour mood.

Used texture brush and applied colours at the side to mimic a milky way.

Applied some cloud with texture brush at the side without obscure the milky way too much.

Added some details at the bottom so it doesn't look too empty.

Adjusted the shadows of the cloud to make it darker.

Added a little details within the cloud to make it looked like it glowed from within. Some more minor adjusts of the colour mood.