So the assembly is almost finished, and then I suddenly noticed something strange when I placed it next to the original:

The width is wrong. Somehow there is something missing on the right side, and there is more space surrounding the joypad than in my design. Which I have not noticed until now. How could this happen?

Well, it turns out the Lynx is just not symmetrical, something I assumed all the time while designing my replica housing. Which you can see here:

The screen is in the middle, but the side-sections start at a different distance from the edge of the screen. And once this is corrected, the front indeed looks even more like the original:
Apart from this there were several small changes that I made to to front, like increasing the hole size for the buttons, so I decided to print it again:

Much better!