Well, you already answered some of my questions. Thanks 
Now the most important thing is - can you share the source code of your project? I work at https://wire.com where we still use Scala 2.11 for the Android client of our product. For sure we will not reuse your code or even update to a newer Scala version (which I find very saddening, personally, but well, too late to do anything about that) but it would be very interesting for me to compare what you’ve done with what I’m using at work.