I think it could be useful to have a checkbox for total listing for the amount column. So if i view orders by a specific status i could get a listing at the bottom for the total value of all those products.
Could be interesting for the stats page as well, toggle which statuses you want to see in a chart (some of us operate heavily on COD, so knowing this info helps us calculate cash flow).
So if we could get a chart (not to replace the total column)
Pending :$XXX
Ordered: $XXX
Shipped: $XXX
In a nice bar or pie chart it would be cool