Cleanup of completed tasks when synchronizing with taskd

After a task has been marked as done, I would like to keep it around for some time, but after a certain period I would like to remove it from taskwarrior, since otherwise the database will constantly keep growing over time. Completed tasks get shifted to completed.data and if I only run taskwarrior local, then it is no problem to move the file at certain intervals to cleanup my data. This is not comfortable though, since I would like to remove only the very old tasks and not all of them. Also, since I'm syncing with taskd, this leads to an accumulation of very old tasks on my server over time, since they won't get removed there (unless I delete all data from the server and reinit). I have therefore the following suggestions:

1) Add a configuration option to automatically delete completed tasks after a certain period
2) Push the removal request to the taskd server in order to remove the file there as well
3) Move the task on the taskd server to a separate database with deleted tasks, so that other clients can also remove them
3) The purge command should tell the taskd server to cleanup the old entry