Akka? Spray? ScalaUtils? Do they take effort to learn? Yes. Are they anything like scala.collections? No.
Why didn't you pick scala.concurrent? Or scala.util? Or any number of other packages? Why didn't you use the signatures in the official docs as-presented?
The Scala team goes out of their way to present something simple and easily digestible to most programmers, even the ones unfamiliar with Type Classes.
I mean, you basically just use a Seq like an immutable version of Ruby's Array and it just does what you want 99.999% of the time.
How often do you see people go on to propose that because much of Ruby's Array implementation would be incomprehensible to 90% of Ruby programmers that that makes Ruby a bad language? It's an entirely ridiculous metric.
If the collections API is purposely trying to confuse people, blame the Scala team, not me.