I think I can speak for EAs when I say overhead is not the greatest metric by which to judge a charity[1]. I understand why it's an intuitive one, and overhead is probably correlated with measures of effectiveness, but if your targets are concrete enough you can just... actually measure effectiveness.
[1]: https://blog.givewell.org/2009/12/01/the-worst-way-to-pick-a...
If I am trying to do the second (influence behavior of others or multiple givings through sustainable orgs) then I would probably donate to Democratic politicians, not EA.
I'm not a huge fan of the org building stuff, and I think the center for EA especially has been wasteful due to SBF abundance, so my donations go to givewell where I know exactly what I'm "buying".
Like there are already hundreds of universities with the abilities to do this or hose a workshop on it. And there's also no special reason to think that the assortment of people they will bring in will do good instead of talk in circles or come to the wrong conclusion. Like - it seems similar to the same thinking a large church does by bringing in religious leaders to talk about stuff?