Originally Posted by
zyrobs
Before the Megadrive, they had home computer hardware, it would make sense that they built the Megadrive to be able to do that optionally. I think they prototyped enough accessories to turn the machine into a full computer, but they went for the bigger option and teamed up with IBM to do the Teradrive instead.
Also, the Saturn had a HDD expansion planned.
If you mean for the Megadrive, they planned on doing 8 palettes and include native sprite scaling. But the scaling made the chip too big and they had to axe it. The extra palette was turned into something that could be hooked up externally, but they never did that except for one arcade hardware I think. System C2? Not sure if any game actually took advantage of it.
I keep thinking that when they made the Megadrive 2, they should've put some of the new features in there, in a backwards compatible way. It would've made it an incremental upgrade, but give the console so much more power.