Wow. This is like nostalgia, directly injected into the vein. I had half to two-thirds of the stuff in Early Champions and Early Hero System when it came out; I remember writing up a character background for a Justice Inc. character (Fearless Findlay, ace barnstormer) that my father found and read. He told me that it was really good.
So, yeah, I’m biased in favor of the early Hero System stuff.