StylePlayer 1000 registered users? I would never have guessed! Yes, seeing the guests would help seeing the potensial of the site. Make all activity visible to everyone. That should also go for the main site.
As for user information, I don't think it will be helpful if you have to go to profiles to find it. I checked out a few of them, and seems that no one exept me have written anything about themselves. Take a look at PSR Tutorial Forum. It has to be encouraged.
Styleplayer.io site would/could/should not compete with PSR Tutorial on general Yamaha keyboards topics, but specialize on all aspects of styles sharing, finding, creating and so on. May be the (future) possibilty to comment on specific styles would create more engagement. If you want all discussion to go on inside the community forum, then a link between the style in Styles section of the main site and Styles subforum could be the solution.