OC has very high quality and art for an anime of its type.Warm colors, defined lines, and very few undetailed faces for when they do wide shots. Almost always high quality.
LN art is NOT favorable in anime. IT's way too sensual, and hard to look at after a while and a reason why its never done. Plus its art made to sell in still format and very hard to always reproduce and draw in anime. Think drawing that LN pic takes a long time? Apply to anime form