Although the VII, VIII, IX trilogy can never compare to the IV, V, VI trilogy, the producers should have kept Abrams as the director for episode VIII after he directed VII.
Episode VII had a certain pace that VIII didn't posess when Rian Johnson took over. After public criticism of VIII, and the decision to bring Abrams back for IX, Abrams was stuck taking over a trilogy he didn't have total control over.
This unfortunately took away from the quality of VIII, and therefor, I believe Abrams should have been the director of VII, VIII, and IX. Then, there could be a fair evaluation of his directorial take on a world-renowned sci-fi franchise.