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).
My favorite OOO to set is something like this: “I’m at sea from X to Y with very limited bandwidth. I’ll reply to urgent emails as soon as possible (but there may be a delay); if you don’t hear back from me by Z, please resend you message.”

My OOO is almost always “I’m out of the office and will be returning on x date.” My email sig has instructions along the lines of “for questions on x, email this list” for a couple of the more common areas people would contact me about that might need an urgent reply (as the lists go to more than just me, obviously), but most people have finally figured out to contact those lists to start with, anyway. If I were in the middle of a project or something that needed to be moved along in my absence, the project teams usually know when we’re out, but I’d put a back up in that case, if needed, but generally there’s not much to be gained by a longer OOO from me.
The bad news is that I’m out of office. The good news is that I’m out of office and enjoying elotes in Cancún.