It is possible to create any number of schedules you wish. You can name each schedule and attach a schedule to a custom mail queue. You can also create as many custom mail queues as you want. Use the Content Filter to move messages into your custom queues based on any criteria you wish.
For example, you can create a schedule called 'Large Messages', create a queue to store those messages, and then create a Content Filter rule using the 'MOVE message to custom QUEUE' action to move messages over a certain size into that queue. If you'd like mailing list messages delivered at certain times then create a schedule called (for example) 'List Mail', create a queue, and then use a Content Filter rule to move messages with an X-MDMailing-List header into the new queue.