Sometimes you can't make all your spacing turn out perfect when tiling on a wall in a kitchen like that. I agree with emily that you should cut pieces to fit and call it good. It will look fine and no one will notice it or think of it as a flaw.

Thank you both! I think I'm overthinking it. How do you feel about an oyster grey grout with the blue? I wanted bronze accents but all the readily available grouts are more brown than I'd like.

As long as you don’t do a super contrasting grout it will never be noticed by anyone other than you. Looks like you did a great job, I would just paint the left wall.

And run a narrow bead of paintable caulk down the wall in the corner when you're done. If you grout that corner, you're likely to have a small crack open up over time.

I did my first tile job 2 months ago in my kitchen. I was going to have a tiny piece either top or bottom due to where my hood vent is...no way around it with my small herringbone tile. I did make 1 mistake on my first wall...no one else (in person) sees it but me. Good luck!! It's fun to learn, right?

Yep, definitely planning to caulk the corners. As well as where the butcher block counter meets the wall. Thanks so much for the encouragement everyone! Really put my mind at ease.