The thing is I don't really want to spend time learning another language. I'm trying to basically be a lone wolf, meaning I want to possess all the skills for game development whether it'd be programming or creating graphics, etc. I just rather stick with Java for the time being, so I can get things done faster.
Do you think it's even worth it to switch from JME3?
Well, I hope one of the guys developing in Java will tune in. Personally I guess JMonkey will have one of the biggest communities you will find in the Java Game Engine world.
But I haven't used any Java or Java Engines for Game development in a long time.
Personally I would not care too much about different languages and go for the engine that best fits your purpose or has the biggest community / best documentation no matter what language it supports.
If you are a good programmer with enough expierience, picking up a new language should not be THAT hard as long as they share common roots (which most of todays languages do, C).
You might find, after an initial uphill struggle to learn this new language, that the new engine might save you time later on because it has features you would else need to develop yourself, because the community / documentation is better, or because the Editor is more intuitive.
But I can relate to not wanting to learn new languages. I hated having to deal with C++ in the beginning :)