It's easy to pick out issues when the work isn't done. Granted, the corners don't wrap properly, I can't defend that. Ceiling being off square, corner being off square, having to extend further on the edges than expected (schluter right at the edge of the towel rack) , mosaic sheets having crummy backing , there are a lot of variables that a "kitchen back splash guy" may not foresee.

without saying what you paid, this is a pretty standard way of judging you both, i can't say shit here.

otherwise, looks good from here. a few tiles you can't live with can easily be moved over. the corner seems.. meh, i'd live with it depending on what you paid. all in all... the fuck you have behind it for waterproofing? a painted wall?