Hi @gwelr, we've thought about this before as well and one solution we're considering implementing is off-the-record messaging which will encrypt your messages so that not even the system admin can see the contents of your message. This could also be combined with not storing the messages for OTR conversations in the database at all, preventing someone from even trying to decrypt your conversation.
I haven't seen a ton of interest in OTR but if it's something you'd be interested in having as part of the product then maybe opening a new feature suggestion for it would help garner it some attention.