Been around here for a while on CA, mostly just lurking... when I not forget to log in for weeks. :D
Anyways, I've reached a level when I'm sort of happy with my works, but want to push things forward, so maybe I could get more comissions and anyways I have still not given up on becoming a professional one day SO...
Please take a look at these (my latests drawings) and tell me what I should pay more attention to, what is weak, how could it be better, etc.
Oh and, just so you know:
I always use multiple references (except when drawing with pencil out of boredom, as can be seen on the first drawing, and on the 3rd drawing where I just wanted to try out what can I do out of scratch).
I have a pretty old tablet with no pen pressure working.
I keep experimening with different brushes.
And yes, I mostly draw fanart.
"More practice" is always the right answer. If your "referenced" works are way better than your drawings from mind, then you need more fast sketches/live drawing/overall experience, so, you can retain what makes a work from reference good.
I dare to say that somethings are already pretty good.
I feel like you're on the right track in your drawings. I agree with the "more practice" advice. What I would recommend, besides gesture drawings, and more referenced works, is maybe try and find some reference with a strong light source. Just to practice figuring out where to place light in your drawings, and how it effects the shadows on forms and figures. I feel one of the things all of your pieces are missing is a definitive light source. Not that you always need an ultra contrasty piece or anything to make it good. I just feel that a lot of your shading on the faces and forms are sort of tentative as far as light source goes.
Also, you'd be surprised how much "presence" a few keenly placed shadows/cast shadows could do for a painting's overall feeling.
I agree with the previous poster that you are doing somethings pretty well, though. Keep it up.