I like the work you've done with your Nexus 7 install. Very clever and well executed! I am currently in the process of doing the same thing with my Nexus 7 and 2012 Nissan Pathfinder, and will be sharing those project details soon.
I wanted to offer some feedback on bluetooth audio. I purchased a TuneLink Auto BT adapter a few weeks ago, and it works very well for my situation. I have it installed in the cigarette lighter inside my console, with a 3.5mm cable running to the AUX input on my factory stereo. The TuneLink also has a USB port that can deliver sufficient power to charge iDevices and my tablet. I like the TuneLink because it will auto-resume my music when I am making short trips. I wrote a review of my initial experience with the TuneLink on my blog, http://www.greatertek.com/blog/2012/...audio-adapter/ . I looked at the BT adapter by Blackberry, and was very close to purchasing it. In the end, I went with the TuneLink and have been pleased with its performance.
When I get tasker working properly, I will check back and see if I can "share" the profile. They also have several shared templates on the developer's website that I plan on using as a starting point.
Thanks for sharing your project!