There are multiple ways to craft your out-of-office message, but there are a couple of standard best practices to follow that will ensure you don’t come back to angry or confused customers, coworkers, or vendors.
We do OOO messages, but also send an email to the department and other relevant people, so that part doesn’t sound odd to me. I want to know if someone is going to be away next week, because then I can plan accordingly instead of sending them an email about something important Monday morning and find out I’m SOL until the following week.

I hate when senders ignore the instructions in my OOO message. Usually, my message is something simple like: “I am out [Dates], returning to the office [Date]. Please contact Jane (jane’s email address) in my absence. General [department] questions may be sent to [general dept email address].” To me that says if you are sending me anything then I won’t see it until I return. If you have something you need to be resolved right away, you can contact Jane or send it to our department inbox (where it should be going anyway).
Use your auto-reply to promote your expertise—you're going to a well-known industry conference, after all. You multitask and use your out of office to connect with colleagues/clients who are also attending the conference or event.