The previous homeowner did a lot of shoddy improvements to the house. When we removed the wallpaper in the kitchen, we realized that it hid that the wall is so uneven/wavy that there are 1" wide gaps between the wall and the backsplash in some areas. I need to figure out a solution before I replace the countertops. I'm not keen on ripping out all the existing drywall and I can't imagine overlaying with enough drywall without ending up with a lumpy mess and weird interfaces with cabinets. Any ideas?