A popular practice with helpdesk projects is to assign new tickets based on a round-robin scheme. This balances the workload between members of the support team. The idea is simple — whenever a new ticket appears, it is assigned to the team member who is assigned the fewest New and Open tickets.
The implementation is straight-forward. When a new ticket is created, the workflow rule checks the workload of each support engineer. The member of the team with the fewest tickets is selected as the assignee.
You can use this scheme not just for a helpdesk, but also for any process where you want to balance the workload. Also, the rules for balancing new assignments can be much more complex. For example, you can assign higher weights to overdue tickets.