Thus far, my favorites are Beat Saber (typically not my thing, but it's great exercise), Superhot (makes me feel like Neo in the Matrix, including rolling around on the floor - the room scale stuff shines here), and Space Pirate Trainer. Vader Immortal has potential, but right now there's only the first episode so it's short.
Oh, there's a free ISS game that's quite good. You can explore the station and go for a space walk.
