[Nexus 7 Q&A, Help & Troubleshooting] br0adband:
If you'd take the time - if you haven't already - to read with comprehension the threads for kernels like franco.Kernel and M-Kernel you'd see a massive if not overwhelming amount of information that you're actually looking for that's already been done. Those two kernels - and probably most of the other popular ones - have extensive levels of research and testing already done on them and in their most currently available forms they are the epitome of kernel development on the Nexus 7, and I stand by that statement even in spite of me not being a developer myself. I have read thousands upon thousands of posts and done my own little amounts of experimentation just to prove to myself that yes, those two kernels (and probably others) provide exactly what their respective developers have worked so hard to provide:

Exceptional performance overall coupled with exceptional battery life as well. Yes you can do your own tuning for your own particular needs and wants and even your own requirements as needed which is pretty much what you're apparently hoping to discover from other people and their own experiences.

I'm not saying this thread is a bad idea, I'm saying it's been done before: hundreds if not thousands of times in the very threads that exist for each of the respective kernels (and ROMs by association). The kernel threads have extreme amounts of info on basic tunables, governors, schedulers, pretty much every last thing you or anyone else could ever do to squeeze out the best they offer and the the developers implement that stuff into the defaults of their kernels based on the results of testing and reports from users implementing them.

The info is out there, you just have to go find it - and yes I note that you said you'd never found any decent threads about the Nexus 7 which is precisely what prompted my first reply: the info is already out there in the kernel and ROM threads.

There can't be a "best of" type thread like this because there's just so many different variations of kernels, ROMs, etc even if the device is the same amongst all the people.

Also, one aspect that most people don't realize: there are different revisions of the Nexus 7 hardware and they tend to perform differently. I, for example, have an original (and I mean first production run) Nexus 7 8GB model that has totally different performance characteristics than the later revisions of the same 8GB model, and then the 16GB and 32GB models are even different on another level because they use faster Flash-RAM onboard than the 8GB models ever did.

So again, it's a great idea and I figured if nobody else ever created one I'd do it myself, but in the long run every device is going to perform differently. Even if you had two Nexus 7s that came off the production line one right after the other and you tested them with the exact same ROMs, kernels, and tweaks, you'd get different results from each one. I'm not being facetious when I say that, I'm being totally absolutely dead serious.

Also, there is no really good overall benchmark for Android, probably never will be. You have to use different ones geared towards specific purposes to get any useful data, like AndroBench which tests the storage specifically and Vellamo which can test the HTML/surfing performance specifically. Antutu is probably the best actually useful overall system benchmark but unfortunately more people use Quadrant which is a shame because that one is so useless the results can vary rather dramatically even if you run it several times in a row.

Believe me, I've been tweaking for decades, so there's nothing I can say or do that'll stop anyone from doing it - I know the bug of "Upgraditis" quite well and have suffered from it forever, right alongside the companion condition known as being a Tweakaholic... :D