I would like to see something like BTC / Hour or minute or day
Daily earnings are already implemented, see Graphs page.
Hourly and minute earnings are not implemented, but - who cares? Mining is probabilistic process, minute or hour mean nothing. Personally I even don't care about my daily earnings, only 7day average (blue line on graphs), which has some weight.
I'm sometimes surprised when people are saying 'pool that and that is paying less than pool this, I tested it for two hours!'. Looks they have no idea how it works and displaying them 'you earned 0.0001 btc in last hour' will make it even worse.