I've wanted to make a language where the memory and the graphics output were interlinked. Meaning your memory was always visible and you had to balance memory usage and graphics usage. For some reason it took me too long to realize I needed to make a VM to make that a reality. Because of that goal, I decided to design the VM around a simplistic goal of having all program memory in one block. While this isn't realistic (a real machine wouldn't have its registers stored in the same memory as stored memory), I decided I didn't care. So in the end, there was one core idea I wanted to play with, but I also wanted to teach myself more about ISA design and explore that area more.