The Lensmen stories were full of many firsts. It was the first true space opera. It was the first sci-fi "epic". And of course, the Lensmen were the first true "superheroes", in classic, altruistic "comic book" sense.
So, you'll find much that you recognize here because you've already seen it from derivative sources. Just remember that THIS ONE is the original and the others are the ones inspired by it.
The Space Patrol of old-time radio, George Lucas' Jedi Knights, DC Comics' universe-protecting Green Lantern Corps, and many, many others all owe a huge debt to these excellent, pulpy reads.