It would be, but cycle perfect emulation is very difficult and costly. Higan (formerly Bsnes) manages it with Snes emulation and it requires a cpu with a rate over 3GHz. I remember reading the N64 would require a 10GHz cpu to emulate with 100% archival accuracy.
long story short, it is the real solution, but its not a practical one by any means.
That would definitely make cycle accuracy easier between all the system parts.
The hard part is for someone to actually develop the emulation for all the custom chips in the system. In particular, the two graphics chips are very complex and the documentation is very hard to understand. The same goes for the sound chip. The others are all standard enough to be reasonably straightforward (if not actually easy).
long story short, it is the real solution, but its not a practical one by any means.