Review Coverage Plugin improvements

What I want from the review coverage report is:

• Show me a graph of how our review coverage is changing over time.
• Let me dig into the detail for a particular period to investigate any unexplained changes.
• Let me forward it to others so they can take a look.

At present it falls down in the following areas:

• It takes a long time for the graph to appear, which is annoying for me.
• It's hard to forward it to others. If I send them a link to the report they have to sit there for several minutes waiting for it to appear. I can take a screenshot and email it but then it's harder to dig into the detail.
  Alternatively you maybe could have an "email me the report" button which would email it in html format when it's finished? That would allow me to forward it more easily.
• The detail report has a rather clunky interface. It only allows me to select a day or a week ("week" appearing to mean seven days rather than any concept of working week) and it automatically refreshes every time I change anything rather than waiting until I've finished selecting what I want. It would be much more useable if I could just put in a start and end date and click a "go" button.