GEM has been on my radar for a few years now, and it just keeps getting better and better. I just wish I had a real project to use it on because it's one of those tools I could get lost in for hours/days/weeks just playing with it. I think it has finally gotten to be where I needed it to actually use it for something that goes further than a conceptual modeler. The team has added the ability to populate your mesh with multiple components before, but now you can aim them at specific points between the base and offset mesh, control scaling of the elements, and control their base datum position relative to both meshes. This is going to be huge for parametric design iterations.
One of the things I like so much about GEM is that it works with just about any modeler out there including Rhino, Cinema4d, FormZ and SketchUp. I'm hoping that Bonzai3d gets the ability to control smooth mesh subdivision upon export soon so we can integrate it into that app better.
Take some time to familiarize yourself with the videos on their Youtube channel. Here's the first one in a series explaining the new features of GEM Elements Edition: