I don't use vault either.
In the morning I check the backups finished ok - rerun any that failed (if I can)
Look in the GUI media and look sort by (hit time assigned once, a hit robot control twice) get all the tapes in the lib at the top, with the once with an assigned date at the very top - these are the tapes used last night.
highlight and eject them,
send them off site with a return date of 2 weeks
when they come back put them in the day after 2 weeks ( if they backed up on a Monday night they will not expire until Monday night - so they would not really be expired until Tuesday -) so have them come back on a Monday, and put them in on a Tuesday- come back on a Tuesday and put in on Wednesday......
real simple
do your media id generation rules and put the tapes into one volume pool (your catalog tapes in a differnt pool) and set your policy to use that pool
remember to set up the backup of the catalog each morning to be done after backups are done, and take it out and send it offsite too.