The ability to make this system agnostic by selecting what races are available in a given setting

[Adagna]

Is your feature request related to a problem? Please describe.
I would like to use this for systems like Symbaroum, or Warhammer Fantasy, or Pathfinder where there are no gnomes, halflings, tieflings, dragonborn, or half-species. But perhaps, Orgres, and changlings are playable.

Describe the solution you'd like
It would be nice to be able to either enter your own races, or enable/disable races that do not exist in your game world.

Describe alternatives you've considered
Even if you can't add your own races, at least being able to disable certain races would be helpful.

Additional context
Add any other context or screenshots about the feature request here.