didn't have time to read all the answers. I have no backsplash and have never regretted it...been over 6 yrs. It is painted with BM matte...which has ceramic in it. It is as beautiful now as it was when first painted. I love the fact that I can showcase other things ...art etc in my kitchen and no competition. Also if I ever want to change it is as quick as a paint brush...expense is minimal..paint only ! All in all I think it is serene as you point out . Here is one pick. Since I have a lot of high heat cooking in my kitchen..built in deep fat fryer as well as gas cook top I can definitely speak to the longevity of paint only. c ( more at this album )

Have you considered wallpaper? You can bring in color, as well as a design, if that's your 'schtick'. Just throwing another consideration in the mix. I personally *hate* a backsplast covered in tile or granite from countertop to bottom of cabinets, or even further up. I've gone *about* 3/4 up the wall, with the remained just the neutral color thruout the rest of my home, but only on the interior cabs, so above the stove and sink areas. On the perimeter bank of cabinets, it's just a painted wall, where I had planned to use wallpaper, but haven't done so yet. I also picked up at an auction a painted canvass, which is long and narrow, and thought of using it here. It's a vintage French scene of a girl feeding chickens in a barn, done in dark colors, which is my preference. I just don't want to leave it should I sell. ;)

I'm not a professional and it depends on the size of the area to be repaired, but it's pretty easy to cut out damaged dry wall and then mud the patch seams. You want to do whatever will maximize the clean, level surface. And, yes, you will need to feather and sand your mud until it is dead level. I wouldn't paint the mudded, repaired drywall before tiling, at least, I never have. And I've never primed drywall before mudding it. If you've only read or watched videos, be sure you practice. If your repair area is large, even if just 'paper', maybe hire somebody?

I agree no need to remove the casing in fact probaly will look odd if the rest of the windows have casing. BTW best to post pictures when asking questions and you post them in a comment here not a new post.