I have a few small features I'd like to see to improve reporting. Nothing urgent but desirable
1. Next to the dates have a pull down list with the options "Today", "This week", Last 7 Days"," This month", "Last Month", that sets the date ranges accordingly. This setting should be remembered between sessions. Have a look at AdWords reporting for an example.
2. Under Items sold, break down the total into the different products, showing sales and refunds, i.e.
Product A 10 1
Product B 13 2
Total 23 3
3. Simplify the ZIP file structure, i.e, give the file a real name (not dl.php) that excell recognises (i.e., report.csv) and don't put it in a sub-directory