I love the idea! I never got too seriously into Core War but I remember discovering it as a high school student and getting exposed to assembly programming. I think that the "natural" language that this game uses is quite intuitive and the whole game is a great way to get started with assembly.

However, I do find the UI quite unintuitive at certain points. Especially when I wrote a program, I couldn't figure out how to run it in the local training assembly.