The problem with pixels...

"Pixels" made up of 3*3 "real" pixels with some color bevel.

...is that you don't really see them anymore. In the age of real 8-BIT graphics, even the pixels were crappy and not even really that square.
Today we can make pretty good pixels, but they are so small you never see them anymore(stupid high-res screens). So if I want some retro looking pixels, I will have to build them from a bunch of lesser "modern" pixels. 2*2, 3*3, 4*4 and so on. But using a homogeneous color looks flat and boring so to emphasize the "pixlieness" it seems to look a lot better/older if you create a kind of "bevel" effect pixel(like the second row of gray 3*3 pixels in the image above). This gives the eye the possibility of seeing individual pixels to get the retro-effect.
Another implication of this is that using such a system would allow me to generate a game that is reeeeeally tiny to begin with and scale it up dynamically by simply scaling the pixels and thus getting a similar experience on any device from a entry level "Hardly smart enough to tie my own shoes"-phone with a 640*480 pixels resolution to the one I ordered a few days ago with 1280*800 pixels.
An old device could maybe use 2*2 sized pixels and a new high-res device 4*4 or higher...