[...] does your state machine really need to be saved at the exact millisecond that the user exited? Or, could it be saved by an explicit user action rather than automatically?
Sometimes, even years after you enter the magical castle, these questions still remain a mystery...
So. Depending on the model, if all the BrS code is doing is hammering the registry to disk, at most it can do that 14 to 43 times per second, depending on the model. But in reality, since channel has to do something else like math or graphics, it can afford to flush once per second or less - with wear-leveling it will take hundreds (if not thousands) of years to wear out the flash => not a real concern; yay for unintended consequences.
Hm, you might want to recheck your math. The way I calculate it, assuming perfect wear leveling and approximately 100MB available for writing, about 6000 16KB writes will write every block in the flash once. Assuming 100K writes per block before wearout, that allows about 600 million writes. At one per second, that's only 19 years. Still a long time, but not thousands of years.