My reply:
1) Someone beat me to the response with this one dang, there are some knowledgably hardware people here..
2) Not needed and honestly any current GPU/graphics card can cream this for overal function..
3)Most older VGA cards offered both planar and non-planar functionality. Planar functionality just fell out of popularity as resolution and color depth increased. The only Amiga that has halfway decent non-planar support is the CD32 with it's Akiko chip.
4)Pinned ports wholy 1960s Batman, USB is the ONLY way to go.. Not even getting into the whole digital versus analog joystick thing.
5) Again things lost to history. However HP just released a touch screen PC with the release of Vista, I highly suspect that has some modern form of Potentiometer..
6)Standard TV signals and their rates of refresh are very well supported. Please explain your comment further..