Can you please elaborate why it is bad to use LC-3 for studying computer architecture? I do understand it is completely different from real hardware, and too simplified. But from the perspective of writing CPU emulators, is it bad for me?
You say you want students to be able to write emulators/simulators etc. (you list a bunch of software.engineering tasks). I say writing an LC-3 emulator won't give you any transferable skills for writing, say, a Gameboy Emulator (still a 30yo system), because these educational arhitectures are bad and abstract away precisely the things that you have to get right to do that, leaving you with something trivial to implement: a C array for "memory" and a few bitwise operations.
Since we're largely looking at the same things and coming to orthogonal conclusions, I suggest we agree to disagree on this one.
Yes, there are fewer instructions.