over colour Poorly composed
Blurry
Indistinct details
Bad proportions
Lacks clarity
Lacks visual appeal
Unappealing
Dull
Uninviting
Unattractive
Poorly executed
Unfocused
Unclear
Poor quality
Inferior
Drawing
Cartoon
Painting 
Mediocre
Lack of attention to detail
Unsatisfying
Disappointing
Over complicated 
Unimpressive