Your post accurately reflects the real thinking of most Americans & possibly most humans as well. But, I will say it again, if they wanted to take over the Earth, they could have done so long ago. It would be irrational to wait until humans developed the technology enabling them to actually resist an alien invasion. The very fact that they've never do that, is the strongest evidence they don't want to. I believe they want us to mature enough to become partners in the already existing interstellar community. They aren't after physical rewards of any kind. I think they seek spiritual ones, much like Buddhist or Christian monks would.
Sure and given the history of our species this is what we knoe and a natural way to think. I have watched New Age thinking appear within the ufo community in my 70 odd years of life on this planet. Your way of thinking is represented in the community very well but also other claims and ways of thinkinh all the way to horror stories. I don't know if there are more than one intelligence involved or if there are eemore than one agenda . The sources of DeLong seem to see threats. At least his military sources. Greer seems to have your opinion. But in all cases the opinions are very human like thinking. But do aliens think like humans? Are they so advanced as to have become immortal? There are even some who think they are after human souls or the containers. You can find every scenario in sci-fi. Of course I hope you are right!