I've wondered about this since 2012, and I'm going to post it here.
What is a game (or type of game) of which you think it's difficult to record a commentated Let's Play? The game itself can be easy, but the LP isn't always so. There could be many other reasons that it would be difficult.
Note that while I don't need a single title, I am looking for something specific. "Breakout" and "Memory match" are specific. "Arcade game" and "Puzzle game" are too vague.
I'm going with Breakout type games as difficult to LP. Whereas in many games you're supposed to find something new, Breakout requires you to make something disappear. It's very difficult to say goodbye sometimes. Still, Breakout games are fun to play.
In theory, the game DX-Ball 2 is a little easier to cover than standard Breakout because you have artwork and extra powers/hazards. But I don't think it's that much easier to LP.