Not an expert either but I have heard others say they make the seem there because it has a tendency to break if they don't because the counter top is so thin there. one seam is more noticeable than the other but unless you are looking for it most won't even notice.

Unless you are willing to buy more square footage of the rock, let it go. Reusing anything is a crapshoot. If the rest of it looks good, then you got really lucky there.

I think it looks fine.

That wouldn't be worth the fight to me; it's barely noticeable. However if your cooktop truly won't level then I would see what they could do

I'm pretty picky and I honestly can't see anything worth redoing. If it's off, it's only off by a hair, unless the picture isn't accurately duplicating what you see IRL. Truthfully, though, it does annoy me, too, when things can be lined up perfectly and they aren't. I mean, why not make it perfect if you can? But most people don't think that way so if you are going to have others do things for you, you have to get over the small stuff and this sure looks really, really small.

I don't see what's off about it. If it's behind you stove, it won't be very prominent anyway. I'd let it go or maybe touch it up with a Sharpie.

Thanks for the opinions. It was just the epoxy that's weird, thick in some places and absent in others. It is off as well, but I figure a backsplash will cover that.

It may be that they couldn't get that side as tight because you had the walls etc redone. For using the same backspash with new cabinets I think they did a fine job. In a few weeks you will stop looking at it so much and forget it's even there.

Mine was like that and I took a razor blade to the epoxy.

"And until this is done I can't get my stove levelled."

A slide in range sits on its feet. The perimeter flange should not rest on the countertop. A slide-in range should be leveled before it is slid in place permanently.