You are too caught up in the details.
I would suggest ditching the 1 pixel brush and blocking things out with a 2 pixel one so you can't fiddle around with the micro and focus on the macro first.
There is no need for a super cleaned up 1 pixel outline if you'll keep changing stuff around anyway.
Don't be afraid to put heavy blacks down where you see heavy blacks.
Afterwards, you go in with the 1 pixel brush and do the polishing.
Also pay attention to where you want to put the horizon.
It plays a significant role in the composition and sets the mood for the picture, a high horizon makes things look weak, lost and insignificant while a low horizon makes them look heroic.