That's what I like about Haskell. Brilliant people writing really cool stuff. I'm constantly amazed by Haskell libraries!
If so, I'm certain there is a simple implementation of the lens idea that's much easier to understand and apply.
"lens" can be complex, but it also makes an effort to fit well with the standard Foldable/Traversable/Applicative idioms of Haskell, and it can be seen as an extension of them, both in functionality and in nomenclature.
FYI, you can omit "pay." if you added it to get https.
No, not at all. It fits extremely naturally into Haskell's typesystem. The fit is so natural that it's quite astonishing they weren't discovered earlier.
If you just had a small subset of the library that only exposed, say, Lens, Traversal and Prism, it would be much more approachable—but would also miss out on much of what makes lens so universally useful. It wouldn't hit all the edge cases lens does and it wouldn't be "batteries included". You'd find yourself ultimately reinventing part of the other abstractions that lens has but, since you're doing it independently and ad-hoc, the result would be uglier.
Do you have any recommendations on what might be a good read or project for learning Lens? I played around with it a couple times, but I could never find an introduction or anything that really let me get a grasp on their core concepts and use. I'm not looking so much for the mechanics of how to use them, but more of an overview of when and why I might want to use them.