Considering Zovaal is said to be Titan plus plus level, the very fact that he is not yet free from the Maw suggests to me that the average Eternal One might be at least a little bit stronger than average Titans. Also we don't really know much of how Zovaal was bound. Maybe he was depowered during the binding process and it took him his gradual increase in power to reach normal Eternal One levels.
But beyond actual powerlevel, we have narrative significance. Blizzard is writing backwards instead of forward. New players are retconned in that trivialize threats before we even meet them. And that is my problem.