Approval Path or Multi-approval Option for timesheets

We have Project Management consultants that work on multiple projects at a time for different sponsors. They currently log their time against each project on their timesheet and each sponsor is an approver of their timesheet. However, if 1 sponsor approves the timesheet, the others lose the ability to approve or deny.

It would be great to have the option of either an approval path on a timesheet (similar to projects/issues/requests) or the option to require all approvers to approve the timesheet before closing it.