I love the 6502, but if we're considering teaching architecture using a legacy machine my preferred choice would be the PDP-11. The ISA is quite nice, and the machine has many of the "modern" features one would expect from a computer, like address translation. On top of that, there's loads of good, historic code to be looked at. Hell, bring back the Lions commentary book!
I don't disagree with you. Any real computer would work I think. But maybe teaching a not-so-good but popular ISA has educational values too. After all we don't know why good things are good if we haven't seen the bad ones...hah!
