Yes, the coffins! Why would they be there?! Or ... wait, it'd make sense if the cycle of repetition is a literal time-space manipulation that the moon simply is too far outside of. Maybe that's the reason? So it's not a simple time jump, it's an all out "Redo of Healder"-change of earth.

Talking about goals more:

So Seele and Gendo needed several "impacts" to bring about instrumentalization. If an angel had ever reached Lilith who lies at the bottom the geofront, that would have caused ... a different kind of "impact"? But then what is the differentiator in all those "impacts"? And why did they keep fighting angels instead of just telling Shinji "yo, my dude, pls go insane and execute the next impage!". Surely, there would have been ways of psychological manipulation.

On another matter: What was Seele actually doing? And why'd they need Nerv? Going by End of Evangelion, they were pretty capable at creating giant fighting machinese themselves.