I had the impression that Berlanti had reached the level where he wasn't day-to-day involved with any single show except to guide its creation and generally supervise the various showrunners. I mean, Berlanti Productions currently has six shows on the air -- the Arrowverse foursome, Riverdale, and Blindspot -- and is working on Black Lightning, Titans, The Chilling Adventures of Sabrina, and a non-comics-based CW pilot called Searchers for next year. He's more like the admiral of the fleet than the captain of any single ship.
Yep. I doubt he will be doing much to change the plans for The Flash and Supergirl. His role is to make sure a Kreisberg type situation never happens again and that all the talent (both cast and crew) feels comfortable with the direction moving forward. It's as much a P.R. move as anything, though. He needs to be able to tell the higher-ups that Berlanti Productions is a good bet for current and future projects.