If you have windows shares you can do what I did. I gave the user that lmce uses to access the shares read and write permissions but NOT modify. This allows lmce to create cd, dvd rips, and add id tag information but doesn't allow it to delete anything. I think this is along the same lines as what Pointman is recommending but with his recommendation lmce might not be able to add or change content. Pointman correct me if i'm wrong.
Also, if you're using a windows share, depending on your OS version, you can setup snap shots of your data and auditing. This way if something was deleted or changed you can easily restore it after being notified by the auditing. I have a 21.5TB storage solution so snap shots are easy for me. Video files, depending on compression, are generally large files (as you already know) so you will require a decent amount of addition, unused space for snap shots. How much space depends on how often you snapshot, how long you keep a snapshot and the over all size of your data.