I see this as more of a real time performance tracker than a tracker someone would want to use for game or demo development...
Sort of true, I guess. You'd definitely be hard pressed to do any sort of demo or game with the music taking about 4/5ths of the CPU time
But NSF export is a definite possibility. LIke I said earlier, there's no technical reason it can't be done as the format support higher-than-60hz refresh rates.
The bigger hurdle, I think, is somehow managing 32kb of music data in ROM. Though having said that, I'm going to have to split up the data into banks anyway as you can only access 8kb of SRAM at a time, even with a 32kb SRAM configuration.