How can we improve WHMCS?

When looking at the unpaid invoices page (/invoices.php?status=Unpaid) it shows the total amount of each invoice, however, if there is a partial payment applied, there is no way to know unless you click the invoice. It would be helpful if I could see the outstanding amount of each invoice in a column next to the total.

Better yet- it would be incredible if there was a way for each admin to re-order the columns, choose which columns are shown, etc. Similar to what you see in Windows Explorer and other similar interfaces.