You may find https://github.com/jonase/kibit helpful for some things. Otherwise I'd recommend just dedicating time to exploring the builtins so that you can resist the urge to wander while you should be programming -- there was a very interesting series a few years back some blogger made that covered all of Python's builtin modules, doing it yourself (or maybe there's one now for Clojure) is worthwhile. I also like to visit things like http://www.clojure-toolbox.com/ from time to time to see if there's anything new and exciting in areas of my interest.
Human has unlimited memory capacity and fast memory access, whereas human logical processing power is fairly limited and error prone. That's why any real human language has a large vocabulary.
Would you prefer if there wasn't such a function to make it easier? You lose nothing if there isn't (or you don't know about it) and gain if there is. Why is this a barrier to entry?
[0]: https://clojure.github.io/clojure/clojure.core-api.html
I really like Clojure, but I've always found the relatively huge set of core functions to be a major barrier to entry. I always have this nagging feeling of "there's probably a core function I'm missing to make doing this or that easier", and end up spending a lot of time poring over documentation instead of just programming. Maybe that's just how it is, and the answer is to push through it until you know the functions better, but there's something to be said for shipping a language with fewer, simpler, more primitive operations.