Awful review. Your comprehension skills are terrible. The source of power was clearly explained as having been derived from Yggdrasil, the tree of life in Norse mythology -- the character of Red Skull clearly being based on Rudolf Hess (and his obsession with the occult).
And if you had any grip on history, you'd realize that Peggy's designation as a British Special Agent is a clear reference to the OSS (MI6 is also referenced).
As for a "rag-tag, multi-ethnic band of soldiers," you might easily be talking about the Foreign Legion...which exists. (Any movie buff might even see this as a nod to the rag-tag band of soldiers in the classic Great Escape)
Further, Captain America does, in fact, have a post-credit teaser (really, did you even see the movie?) It's one thing to have every historical reference sail over your head, but you're even factually wrong. Time for a correction...
The problem isn't even a matter of your ignorance of the comic book universe; You barely have any concept of historical context. Must you have everything spelled out for you?