Hi, Tiles, paint, glass splashback or using the same worktop effect as a splashback all depends on personal choice as this is the space you will be using and seeing daily especially if you are a real foodie. If it is tiles you are wanting, I wouldnt tile to the top, I think it may be too much Especially with metro tiles; rather I'd prefer to line the tiles with the window bars and see if the extractor can be lowered by a notch to ensure there is continuing straight line through out. Alternatively, I'd consider a neutral coloured glass splashback behind the counter space which would co-ordinate with your walls and work surface.... Good Luck

I don’t feel a prospective buyer would worry about one cracked/broken tile to be honest. Nowadays people usually update a new home to their own taste. I would remove the tape unless it is a trip hazard as that will only make it look worse.

Walls and Floors have these https://www.wallsandfloors.co.uk/white-tiles-white-floor-tiles-15072 https://www.wallsandfloors.co.uk/matt-black-white-floor-tiles-black-floor-tiles-15071

My bathroom looks to be about forty years old, judging by the dated tiles. The tiles are awful, but the shower grout looks fine! If you like the small format tiles, I wouldn’t necessarily assume they can’t also go in the shower.