This is essentially the "system" that is used now. The symbols are really even the same (with the exception of satoshi as I have never seen that symbol before).
As of now, I really don't see any real need to measure bitcoin in any unit of measurement smaller then mBTC as bitcoin is not valuable enough for one additional .1 mBTC to make a difference in the actual price of something.
there is a definite need for these different Fractional Units...
for pricing shitcoins poeple use satoshis.
for small ticket items some sites already display prices in bits or mills
the problem is there is no clear definition of what is what, for example on bitcoin qt 1/1,000,000th of a bitcoin is called a micro-bitcoin, on blockchain.info's wallet they call'm bits
who's correct?
what's what?
these are the things that keep me up at night! ( not really
)