sprite editing tool

16 bit is the worst of both worlds. It's twice as bulky as 8 bit, but you're almost guaranteed to lose colour information because it's not indexed. Either don't use more than 256 colors in a single image for low colour styles, or go straight for true colour.
Plus it's like, 5-5-6 bits for the channels, nobody wants to decode that

 

Oh, I don't think we were talking about 16-bit images, I believe Walrus_Guy was referring to 16-color bitmaps, in other words, 4-bit images. If you don't use more than 16 colors, it would be efficient to save it in 16 color format.

 

Oh. Yeah sure but paint.net doesn't do that either.