I not too familiar with this critique system personally nor good with words in English so I made a little over-paint on the upper part.
I not touched your proportions nor the shape of the forms but played a bit with the lights and shadows to make it ways more outstanding yet not overdone with effects-colours.
Since I did see you try to make the distant parts go in the distance with make the toning more greyish which helps to give back depth I used this way to make over-paint. You can find it right here (and hope the link works);
I am better visually then with words, hope this can help you a bit!
i see what you mean, thank you for the constructive feedback.
i gave myself a timeframe of an hour for both pics, so it looks still very unrefined.
although, with better technique a pic like this could be much better within one hour. i go on trying to figure out how to do it right.
If you think about concept artist style of quality in a hour long work then you really should turn to photoshop and use PS brushes as concept artists use a LOTS of texture brushes (such as grunge, dirt, ground, earth, grass) which not make the art be faster but it makes it look ways more refined for little time behind.
Or painter (but this is where I use artrage as painter too big for my machine to handle, also ways too complex to understand) which by nature gives artistic texture on the brush tools.
What I suggest you to put more attention on is your contrasts because it is very weak. To control it keep put your work into grayscale and see how much with only greys it stands out. That also helps you to give more depth in your works once you can balance your contrast use )