Could you tile to the ceiling and put crown molding up to cover uneveness

I think the area where unevenness will be most noticeable is under and around the two windows. If tiles are laid horizontally, it will be noticeable. I can stop tiles 18" up or extend to the ceiling where there is crown. My biggest concern is just how to minimize the noticability of unlevel windows. Would a herringbone design help or would that be just as noticeable?

Xerox or print out a herringbone pattern. Tape some sheets together and hang it up there to check it visually in your actual location.

If you wanted to do an art project, cut paper into your tile size. Use some painters tape to put it up piece by piece for some fake tile and grout spacing.

I love the pattern and think it would help.

I think it would help, but bmore gives good counsel. Try it!

bmore always has good ideas. Here are a couple more. First questions - how out-of-level are those windows? Are they new-installs? Can you post an image?

First of all if a window is not level and plumb, it's not going to open properly. You know it should be fixed and you really should do this before you install tile. But if you're dealing with a 100+ year old house and windows that have been there forever, and you don't want to touch them I get it.

Can you level out the window trim a little so that it appears less out-of-level with the counter without looking too tilted to the window? If so, any option you pick will look better.

Herringbone, that I love by the way, may be fine but it is a very linear look again. It may not be great in your space. My guess is that avoiding lines altogether is the way to go, so pick marble, but consider a mosaic that uses rounds or octagons, and yes, if you can take it to the ceiling that would be great. I know this will be a departure from the look you wanted.

I love this tile, and at least one GWer has used it. It'll give you an idea of what I mean. mpagmom's bs:

You don't have to use color, but if you can get away from straight lines, you'll be happy you did.

How about using a Carrara random linear mosaic but run it vertically instead of horizontal. With the mosaic vertical, the pieces could be cut to fit the unevenness. The uneveness wouldn't be noticeable because the horizontal grout lines would be random so there would be no straight across line that the eye would see as being off level. My ceiling's were level but I ran my glass/stone mix tile vertically because I liked the look. I get lots of compliments from others saying it looks great that way. Here is an example of some Carrara tile that I found
{{!gwi}}

And here it is vertical
{{!gwi}}

Oh - also, can you add a stool that is level (its what the gods call an inside sill)? Sometimes, if the window has had an extended stile added to the bottom, you can take it off and then add one that is level. It just moves the "unlevelness" back to the edge of the window - but it may be less noticeable there.

You can check that with a simple board and jazzy tape before spending anything.

love all the tile pics

Herringbone should help. With a herringbone patterns joint width isn't as noticeable as with a linear pattern. This should give the tiler some latitude to pull it closer to alignment so it isn't noticeable.

I have a herringbone floor in 12x24 tiles. They made sure that the most visible edges didn't have points lining up along the edge and they subtly shifted the tiles to pull things so that other edges looked good as well. I am not talking about much variation but even 1/32" over 32 tiles gives you 1" of shift.

this may not be a look we see often on gardenweb (i think firsthouse_mp did this and it looks great, IMO), but what if you did a solid slab of granite backsplash that is same as your counters? then there would be no lines to see.