Personal workspaces are designed to be used personally - this is enforced where personal workspaces do not allow more than one member to be invited on the workspace itself (but you can invite people and collaborators to manage drives, folders, and files).
Team workspaces however, are designed to be used with teams - you can invite multiple members to workspace so they can have quick access to multiple drives, share drives, manage inheritance permissions, access and edit permissions, file locking, shared searches and more.
This is why we recommend that if you plan on using Shade for a team at all in the future, you should always set yourself up for a team workspace.