@pgh550 it would be ideal if you could go back and update your original post with the current DSDT that works with 10.11.6 (if you are using that). I know Sierra is about to come up and we'll all want to be on that, I personally don't care to be on the beta cycle of OSX.
The DSDT that is currently posted in this thread does not appear to handle the adaptive brightness or the battery correctly in 10.11.x. I have been out of the scene for several months since I gave Ubuntu 16.04 a serious test run, ultimately I left again due to a lack of professional and creative software. The OS was just as good as OSX imo, but the software is lacking for a creative professional.
So here's the DSDT and the kext files that I am using, and while the brightness keys do control the brightness ok they do not trigger the OS brightness overlay. They used to in 10.10.x, but I never could crack how to do it in 10.11.x awhile back and I haven't given it another shot.
EDIT: I do not recall what all patches I applied to this DSDT, but I know I had discussed various things I had done in this thread to get it to the point it is at, but still I did not ever list all the patches applied methodically like I should have and at this point it would probably be easier to start from scratch and I do not have time to do that atm.
I continued to use your config.plist with an addition of -v on the boot parameters. I have also grabbed the latest Rehabman kext files to get broadcom bluetooth and wifi working. Previously I had some stability issues, but I believe most of it was related to using displaylink drivers on my system to drive a 2nd and at times a 3rd monitor. On another note after running Ubuntu for about 6 months I can say I had fewer freezes, but overall I would still get some odd kernel freezes and end up with a system that would not respond to the touchpad or reboot commands. It makes me feel better about the OSX build than I did previously, and even with additional freezes I would rather put up with it than the lack of particular software. Ultimately, in a few months I am likely to upgrade from this and my Macbook Air as having something rock solid stable is important to me.