Seems the tile gurus are in this forum...

Doing a kitchen remodel and the GC is a small do it all kinda guy. As such he was great with the cabinets but I am uneasy with the backsplash. A few things looked a little off and after doing some reading we are concerns. Right now 3x6 tiles are installed with a 1 inch accent strip. He has yet to do the grout. Trying to determine if we should let him finish with the grout or reassess.

Issues:
1 - all of the tiles are not flat with respect to on another. If I run a board across they catch the edges of adjacent times. Worst looks to be 1/16 to 1/8th.
2 - the wall was uneven to begin with and he did not prep it level first. If I place a straight edge along it, I can see bowing of 1/8 inch or more. Could this cause the flatness issues? Should it have been prepped better and will it cause any problems later
3 - he placed the tiles directly on the granite countertop. No spacing at all for expansion. This is a huge concern to me as we do have some heaving from season to season.

Just not sure what to expect in terms of install nor what to expect in terms of the cost for replacing the already installed tile should we want / need to start over.

I've tried to attach a few pictures...

So, do we fix the worst offenders of tiles sticking out, live with the risk that there is no expansion gap to the granite and let him finish with the grout and see how it goes? Or find a specific installer and have him start fresh? If we do the latter do We eat the cost of the material or expect him to?

Thanks in advance...