hehe thank you brother <3 , maybe for others these "issues " may not be visible but for my it is there, Could be like low quality modeling cause my modeling skills not that strong so i always try to make up by adding texturing or play with lighting or DOF.
yeah we use 2D elements in 3D scenes such as Mattepainting, I also noticed some cartoon shows that its 2D, but they are using 3D Backgroungs, i think theres always a nice mix btween both worlds