Empty state design for serious brands

I'm designing some empty state screens for an airline/train travel app.

I've looked at quite a few examples and what I noticed in most cases is some humour in the copy or some kind of characters are used for visuals. Of course this is to minimise user frustration when users reach this screen.

My question is: how can this be applied for companies that don't want to use humour or funny characters? Any examples would be appreciated.