Thank you for trying the app and for the suggestions!
I'm definitely looking to expand and improve the dice interface in the near future. I would like users to be able to create their own favorite rolls and save them as buttons. Having all the dice buttons in the dice popup sounds like a good idea for that.
The reason for the scrolling Oracle buttons is because I also plan to support custom tables in the future, which means users can add buttons for their own content as well as external tables from Chartopia. So there may be many custom buttons mixed in with the standard ones. Issues with the scrolling have been reported a few times and definitely needs some work.
The "Game" action button may get turned into "Notes" in the near future to support things like lists and character sheet references.
Markdown would be great, and I did look into that. The Godot game engine that I'm using has great support for BB Code and almost zero support for Markdown, however. So it's likely to remain BB Code for the time being.