This pic doesn't have the favs it deserves, I'll do my part to change this situatiobn. I wouldn't be able to get animal anatomy right in 15 hours, let alone 15 minutes... May I suggest that you submit the pic to some groups, so it can be seen by more people?
if you're taking too much time to have something done is probably because you are focusing too much in the mechanics (finish this, then this... etc) Try too loose a bit... try star drawing without follow any specific process; for example: color directly over a very quick sketch, "overwrite" instead of erase and add details only after some time later. here [link] what I did without use undo button.
Also thanks for the suggestion, I am not experienced in dA ways but surely groups to promote looks like are a good idea.