There is a need for better notation, that doesn't get out of date fast.  millis, and micros etc are too awkward.

My suggestion for how to describe sub-units of coins is to use Log10 notation:

BTC1 = 1 Bitcoin  (The existing format)

1BTC1 = 0.1 Bitcoin (i.e. 10^-1)
2BTC1 = 0.01 Bitcoin (i.e. 10^-2)

etc.etc.

In this way 8BTC1 = 1 Satoshi

So, for example if you wanted to sell something for 0.0075 bitcoins you would say 3BTC7.5  or 4BTC75