There is no change to Bitcoin required to implement this. Whether someone implements this does not "improve" bitcoin.
Use whatever unit YOU want in YOUR application. No consensus is required. This is best solved as a client-side user preference setting. Not a BIP-worthy proposal, IMO
if a gazillion people show up tomorrow and decide to call satoshis arthur, there's sod all anyone can do to stop them - silly, pointless BIP trolling is an irrelevance - anecdotally, it smacks of the same kind of presumption that's been causing so much trouble lately.