I would add full IM capabilites. Not only WhatsApp or Skype, but everything: GTalk, AIM, Yahoo, Facebook chat, etc.

If it can't be fully integrated to Telepathy (I'm assuming they're using that) at least they should do a *very gorgeous* port of pidgin.

And if they want to sell the phones they would need to attract regular users with also gorgeous native clients for Facebook, Twitter, Instagram, etc.