OK - I also set the GW folders to purge immediately, as the queues see a lot of file creation and deletion. Maybe marv can add if that is a good idea or not.
Be sure that users have no rights to the database. It is possible to run it as a fileshare database but it is a horrible idea to actually do it.
GW is extremely stable, so if you set it up according to the guidelines and taking Marv's advice it can literally run for years without failing. I have seen Exchange installations of 100 people with a full time mail admin, but with GW I have seen a 4000 user 9 PO install run by just one person.
You will want to do the general mail system things like control incoming attachment size, antispam and antivirus, etc.
As a matter of procedure I whack the indexes and also do a top-down rebuild twice a year which is adequate for my small shop.