How does someone create the first type?

They need access to the type > create permission

Which means that you need to grant them that somehow.

The Type node doesn't have that permission by default...

So we need a way to grant that dynamically, it seems.

We want people to be able to create their own types.

Maybe the solution is to use groups. That way you wouldn't need to hardcode
anything.

So what are the permission groups?

Does that imply a change to the permission type?
Account OR group.

And group is a type.

And people can belong to a group. via the account list