It's an interesting idea, but not really feasible. A Gamecube or PS2 has far, far more horsepower than any of the 2D consoles had, and they can be bought brand new for $100 and $130, respectively. Just because they can do 3D graphics, doesn't mean that their games have to be in 3D. I can't see anyone being able to design, produce, and sell a new console that could undercut these two systems.
Genuine question and I mean in terms of game quality, not tech specs.
If technical specifications aren't important, than all of the consoles are pretty much equal. For any particular genre, there are damn good games on the NES, SNES, TG-16, NeoGeo, Genesis, etc. Some may look better than others, but that doesn't make the game any more entertaining or of higher quality. If you equate game quality to scaling, rotation, color count, parallax, or similar things, then you are actually talking about hardware capabilities. Based on objective abilities, the Saturn is the best 2D console as it is easily the most powerful (not surprising, considering it's also the newest).