Hi I'm one of the founders of Outerbase, just want to clarify a few things, seems like you might have some wrong information on Outerbase.
Big fan of Mathesar by the way!
1. We have a incredibly powerful CRUD editor on our table, in fact you can drag and drop and select multiple columns & rows, I haven't seen many other DB editors support this.
2. We allow you to pick foreign key constraints from a dropdown as well.
3. This is true.
4. Outerbase is open-source with more and more features heading into our core offering there. https://github.com/outerbase/studio