I personally choose Java/SpringBoot, it has a steep learning curve, but has strong typing, runs as fast as most C++ code out there, plus you can do async.
and if you want something fast but that is as easy as Rails and runs on Java/Groovy/JVM, use Grails.
That doesn't seem easy at all. Immediately I am presented with 5 choices and then a list of 50 things that I might want to add to my application. Some of those 50 choices seem to be mutually exclusive and I don't have any way of knowing which I might want or why.
Rails? Just rails new myapp.
Build system, Language, Spring version, Java packaging, Java version
The rest is naming.
That is not complex to me.
As for the dependency options... well, they are dependency options. I'm sure you have no problem with adding gems to a rails project, even though there are thousands of them that may be mutually exclusive! A non-ruby dev might not know which gem they want and would have no way of knowing what they want or why!
rails new myapp is exactly the same as doing this with no dependencies.
Is there a reason you'd use Grails over Rails on jRuby?
Note: I see that torquebox was discontinued. It was a simple way of getting your rails project to work with JBoss and had many nice utilities like infinispan and stomp. Good old days.