It requires much complicated gui also for people not interested in monitoring each workers separately. I also though about this but rejected the idea of 'subaccounts'. But you can register multiple accounts with same email, so feel free to create more separate registrations for each worker...
But then I can't monitor them together. I understand your 'strategy' of not complicating the gui though. What about generating the additional worker's estimated reward column in the webpage and leave it commented, ready to be uncommented for users that want it with a 'pimping' script like dacoinminster's script ?