We appreciate you taking the time to submit your feature request.
Having the option to sort by chronological date on a pick list would be a useful feature. I will definitely pass this feature request over to our product team. In the mean time, have you tried adding the order date to the column section and grouping by order? After that has been applied we have an option to export the pick list as a CSV file. From there you should be able to sort within Excel by the date the order was placed. This might be a good alternative for the time being.