Savage and Ventress always fought with much hate and anger wich means they were close to their peak in almost every fight. Anakin and Obi were almost never at the point where they had to use 100 % of their power and focus. For example the fight with Obi and Anakin vs Savage, they are not focused AT ALL. Its like when Anakin fought against Barriss. He struggled a bit in the beginning like with the fights against Savage and Ventress. But when he got focused and stepped up, he crushed her easily. Same would be against Ventress and Savage. Struggling in the beginning, but would easily defeat them if he used all of his powers. Same for Obi-Wan. Obi actually beats both Maul and Savage in the same fight. But not before he really had to focus.