The right-hand part of the image is an example of the undesirable 'blotchiness' that is looking bad. Doesn't look too bad here, it's true, but this is the best one by far - some look really awful, and it only takes the slightest shift in light to go from acceptable to complete crap. There's nothing wrong with the basic construction of the thing - it's all put together pretty tightly - not sloppy at all.

For anyone reading this (I know there aren't many) who might be working on a small stop-motion project, it's essential to have lights and a camera on the go when doing the finishing work on a set. The actual set looks nothing like this at all; the camera sees very differently than the eye does.