I'm in the minority that thinks some of these shows...can just be a good story on there own. We don't need every character getting a call back or be a major part of the show. If they want to do flash backs and have Ashoka pop up cool, But at least from Rebels, it doesn't seem like they have talked since Clone Wars.
Obi wan to me is going to be less about connecting dots and more a way to just have some good actors finally get a chance to do so. The Prequels acting sucks because they were directed so poorly along with the bad writing. Now its time for these actors to show off and be like "yeah we could have been even better if the prequels were written/directed by someone else"