I have a hard time understanding why the IRS doesn't at least have a basic web portal for individuals and businesses to do simple things like update addresses, send secure correspondence, check on the status of correspondence, file forms electronically, etc. A lot of paper forms and letters, human resources and time could be saved with such a system, even if it doesn't actually provide for any tax computations itself…
They do have such a portal which does some of the things you list and several other things too.