You have problems with arms, hands, and shoulders. Specially when setting the arms in non-resting position. The shoulders, doesn't sprout from the arms in a manner similar to road signs characters. The "package" in males bulges in their underwear. Specially when using loose underwear made of thin cloth.
Check for clavicles and the rest of the bones in google. Check for practice models here in the DA in the photography category. Or use family, and friends for it. You are already taking your time to make a comic, so there is literally no excuse to say you have no time/money to improve. Also, I don't give a damn it took you 7 years to "master" colours withouth help/education/lessons, you have problems which reduces the quality of youyr work. I don't have to explain to you what does low quality make to your work.
A particular mistake, best explained using this piece kitsunefire7.deviantart.com/ar…
. He's supposed to be holding the girl, but his humerus part of the arm (look that up) is not representing the proper forshortening to represent him holding the girl. Since the light doesn't help adding tridimentionality to it. Also, you seriouisly need to stop painting over the scan. You need to start doing inking. I suppose you are using photoshop. Photoshop has both brush, pencil, and pen tool. Outline the scan on a different layer. Once finished, you have a clean lineart easier to paint. You can also increase the scan size so the line art is finished with enough room for details. There is a workarea tool to resize the "page" you are working on.
You already have there several issues you have to work on, and a plethora of options to rely on. All you have to do is to do it. No excuses. Otherwise, no tears and complains if anyone ever calls your work bad/mediocre/etcetera/etcetera/etcetera. You already have times for this, so there is no excuse for avoidiung improvement.
What do you think? Is he right? Go comment on his comment box, in my features page to let him know.