Well, here in the original forum post covering the release of VexCode VR, @tfriez specifically mentioned that
Playgrounds include a grid map, an art canvas, and a walled maze. Many more will be added.
Different threads have included more playground releases, so this promise is obviously not empty.
Going off of the old Virtual Worlds (which is somewhat relevant, but not particularly), there was about 30 (maybe?) different challenges and playgrounds, so I think that in order for VexCode VR to continue being great, there needs to be a lot more playgrounds. I believe they have more activities in the works.