Why not just use Scala? I'm not a Java progammer and have no reason to become one, but I've been looking at Scala recently and it looks very interesting. I am a C# progammer and F# is becoming more and more compelling.
That's what we decided!
And now that's what we do.
Horstmann wrote "Scala for the Impatient" (great book) and presents the issues around the language and tooling pretty fairly
Of course there are things which are not quite simple in both languages, but in Scala those things are features which actually enable me to solve issues, not some language design failures from 1995 with which we have to live now for the rest of Java's life.