Edited by javimotta98 at 2016-5-31 01:45
OK, I have good news! I've found the cause of low OpenGL ES performance. It's all because of the compositing window manager, the component that draws windows and their borders. The composite manager used in MATE desktop isn't compatible with OpenGL ES. Because of that, the composite manager is software-rendered, so all things that are shown on screen passes through this software-accelerated compositing manager, including all the frames generated by Mali GPU, causing a bottleneck. Disabling the composite manager results in a huge boost in OpenGL performance. For example, the 3D horse test from glmark2-es2 benchmark goes up from 44 FPS to 82 FPS and now it scores 77 points. This problem is also present in other distros, like Ubuntu MATE from melanrz. Some other distros, like Lubuntu 15.10 from the Orange Pi russian forum, don't suffer this problem because they use OpenGL ES compatible compositing window managers, like KWin. So, if you want the best 3D performance, just disable the composite manager in MATE Tweaks. There are some drawbacks though, like losing shadows in windows. I will probably switch to other compositing window manager in next release, maybe KWin. What do you think?
Apart from that, I haven't found any more performance-related problems or bugs so far. I think it's stable enough for everyday use. I will edit the first post to reflect that. In next version I'll also try to include Kodi. What else would you like to see in next release?