Top Down 2D Camera FoV and Player Pixel size? Thread

Hello, I was wondering what is the standard FoV for Top down shooters. My game is a 2D top down shooter without perspective. Also what is the player size in general, I am trying to have good stable performance but still nice images. Should I go for 128x128 or something more bigger like 320x320 or relatively small like 64x64.

Thank you so much for your input. (All work is done in Unity 5)