None of the things you're looking for are going to help your team much unless they already have a good understanding of relational DB theory and some experience

None of the things you're looking for are going to help your team much unless they already have a good understanding of relational DB theory and some experience. That being said, I do like DataGrip by JetBrains for general SQL usage. Visio is fine for generating diagrams if you've already got licenses, though there are far better products if not.