I suggest you explore avantfax, IMHO it is more functional and you can manage the ouutbound call queue (Elastix 2.0 promises better function in faxing)
There is also a faxrm command which is part of hylafax to remove a fax from a queue and faxqclean for more ordely management of the queue, they both have man pages.
For the processed pdf's I suggest you look into a cron job to do that for you if they become unmanageble. the daily and hourly cron jobes in /etc/cron*/hylafax can be modified or supplemented
As can /var/www/html/fax/includes/avantfaxcron.php for avantfax
I installed the great Elastix 2.0.2 and Avantfax 3.3.3 all is working fine but can seems to delete unfinished jobs from outbox. Anyhow has a solution to this? Even when I manually run the cron, nothing seems to happen. Please help if you have a solution here. Thank in advance for your contributions.