Does painting over stylized wall tile in bathroom look good?
Will they look OK?
Beauty is in the eye of the beholder.
If a buyer likes how it looks you are golden. 

Here is a portion of an article from Sherwin Williams on painting tile.


  Most ceramic tiles can be painted, as long as it's not frequently subjected to water or heavy wear. For instance, you can paint tiles on a bathroom wall, but avoid painting tiles that line a bathtub, shower, or that is on the floor or a countertop. Frequent exposure to moisture could cause the newly applied paint to blister and peel. Heavy abrasion from foot traffic or countertop use could cause the paint to wear prematurely.
  Many experts have doubts about painting tile because the results can vary, depending on the type of tile, the products used to refinish them and the process followed.