Redesign the backend view of the block
Visual feedback, when entering the Instance-URL.
Visual feedback/search results for user and group filtering. Maybe use https://developer.wordpress.org/block-editor/reference-guides/components/combobox-control/
Evaluate the backend view in general, what should be displayed in the block, and what should be a setting in the sidebar (block-attributes).
Deleting a branch is permanent. It CANNOT be undone. Continue?