1) To create a more social connection with others that use Bitcoin miner is to create a chat funtion inside the app.
ofcourse you should be able to enable or disable this funtion and only works in fullscreen.
The account can be connected to the account they make here on the site. so you dont have unknow account and also good for moderation of it.
3) An option to make a x % donation of the satoshi you mine for developing.
4) A share button to share your mined satoshi on facebook, twitter or google+ ( maybe more platforms)
5) show total mined satoshi on the miner page. Connected with the bitcoin adres they put in.
i had some more but forget those :P
Bitcoin Miner has been discontinued. Please see https://www.groupfabric.com/pool/ for shutdown information.