Hi Jaanus,
The Voice Channel already does something similar to this. In the event that a contact has reached an agent before if that agent is available it will offer the call to that same agent again within a 24 hour period.
If the agent is not available then it will go to the next agent.
You can increase the odds by heavily weighting the importance of agent priority in the Voice Channel Customization.
We personally ran into this issue with a contact center that had a lot of repeat callers. The same agent was always getting the call over and over again.
In that case, we actually developed a script to remove it from the preferred agent offering from the CAD before delivering to the queue.
Thanks,
Marcus