Very interesting concept. I look forward to the followup(s).

I've looked carefully and don't see any mention of what version of Windows you are testing. I "assume" Win 8.1.1, but ... it would be nice to know for sure

I know it would be a lot more work, but I think it would be interesting to see at least a cursory comparison of SOME of the tests using more than one version of Windows on the same computer, ie Win 8.1.1 vs Win 8 vs Win 7 vs Vista (?). It would be a way of confirming claims that Win 7 and Win 8 are each "faster" than earlier versions.

Since you have the "optional" hands on component, how about encouraging people to report on their test results and then you could create a summary of interesting results, ie outliers and "average" results. Define what info you would like to see, ie hardware (CPU, RAM, HD size, HD rotation speed etc) and OS.

As well, although it is implied, I hope you will encourage people to make and KEEP an image copy backup of of their "tuned" system so that they have a good starting point for future OS re-installs. Especially in Win 8(.1.1) they should make "recimage.exe" backups to use with the Win 8 "Refresh" feature.