Thanks, FRiend! Good thoughts!
I think I'm inclined to shy away from scented things, unless something presumably innocuous, like, maybe, vanilla, or perhaps something that smells like an apple pie, maybe, because some people are sensitive to scents, or just plain don't like them, and I don't know the two new colleagues that well just yet.
I have something similar to your scent diffuser in my kitchen, a gift from a cousin a few years ago. It plugs into a wall outlet (it has an on-off switch), and you put little squares of some waxy stuff in the cup on top, and the heat melts the waxy stuff and makes my whole living r00m-dining room-kitchen smell apples and cinnamon.