Most PC games nowadays obviously come with the standard option to change the game's resolution from between 640x480 to 1920x1080 on average, depending on your monitor and whether or not you are playing in windowed mode. However, when developing a retro pixel art game, allowing the resolution change to be between 640x480 and 1920x1080 is rather absurd.
So in a pixel art game where, at default resolution, one frame of the main character's sprite is 16x32 pixels, what would you like to see the game's default resolution to be, and by how much would it scale with each resolution option? Would a square screen be better than a widescreen? How many map tiles (at 32x32) would be best to display across and down?
So, in general, what would be the optimum game screen size and at what resolution for a pixel art game now? Your opinions are appreciated.