Groovy's problem is that it is the "anything goes" language. There is the eternal September problem of new people entering the industry, and for the first ten years of a person's career they think that more complex, more verbose, and harder is somehow better. Groovy provides syntactic sugar for much of java, but that is going to be seen as a negative for people who compulsively have to type out long form code or use the most complex language feature they can. In ten years people would have forgotten about Groovy, because Python has already won over so many communities. No one complains that Python is slower than Java or not as complex as Scala.
I have been looking at web frameworks on JVM's a little bit lately for work (yeah doing coding again). My most recent experience has been doing some hobby projects with Ruby and Rails framework. I like how that works for simple CRUD apps, a lot less mundane coding is needed compared to my programming in Java web apps 5-8 years ago.<p>There has been some decent research by Raible Designs on this topic: <a href="http://raibledesigns.com/rd/entry/grails_angular_vs_jhipster" rel="nofollow">http://raibledesigns.com/rd/entry/grails_angular_vs_jhipster</a> or <a href="http://www.slideshare.net/mraible/comparing-jvm-web-frameworks-february-2014" rel="nofollow">http://www.slideshare.net/mraible/comparing-jvm-web-framewor...</a><p>I don't know the author but those articles have led me towards looking into JHipster. Grails didn't sit well with me since I have done Ruby/Rails prior to that and some things just appeared backwards with Grails.<p>My personal results recently were that JHipster was a bit cumbersome to get going since there are so many dependencies to install. Some of which I could not get to compile/setup with Node.js. Since my target app is an enterprise corporate environment, that is a non-starter. I'm leaning towards Ruby/Rails but with JRuby and the warbler gem to basically WAR up the Rails app so I can deploy to something simple like Tomcat.
This is really two questions. Or maybe three. Can you edit it to be a single one? Personally, I'm most interested in the Grails part and I'd probably weigh in on that, but I'll see which way you take it.