I often post under your drawing short comment of one or two words, for example "very good" or "great". Those comments are not simple compliments, but are also valutations.
I make a comment only when the valutation is positive, so even a "not bad" can be considered a good thing. "Not bad" corresponds to the enough.
Now I'll explain you the scale of valutation.
Not bad < Nice < Very nice < Good < Very good < Great < Wonderful < Masterful
And remember that an exclamation mark corresponds to a +.
Comment without exclamation mark < Comment with exclamation mark!
But remember: this valutation is not about the technical level of your drawing, but are about how i like it, based of my personal tastes. So don't take them too seryusly.