One of my favorite gifts to get is gameroom decor. Stuff to hang on the walls, etc...
I have a guideline that I can only hang up things in the garage that I got on a trip or that someone gave to me. I can't just go to a local store, buy a bunch of stuff, and hang it up.
I like to look at them and remember the story, or the person, behind them.
Another thing to consider would be pin "extras" like Arcade mentioned. If they don't have a pingulp yet, it's probably because they've never tried it or spent the money on it. Same goes for BentPlastic, lit flipper buttons, etc...