It'd be really helpful for testing to know what bugs have been (or are supposed to have been) fixed for each new iteration of PBE so that players can test to see if they are truly repeatable and also restate what bugs remain from previous iterations that still have to be fixed.
Additionally, getting information from data-mining sites often breeds misconceptions from incorrect or incomplete data. It'd be helpful to know what specifically is being tested on PBE from Rioters both in order to focus testing on those elements and to also stem the ill-informed reaction threads that make it hard to get informed discussions. I wish that the stickied threads were up-to-date with the constant PBE changes, but it seems like not all the data is correct; I just checked the AD on SoEL and the AD on PBE is 30 as opposed to 25 like the stickied jungle thread states.
Edit for clarification: The point of the notes mentioned here would be primarily to identify what bugs have been fixed with each iteration of PBE, which would narrow down what bugs remain and also focus testing on making sure that bugs that should be fixed truly cannot be replicated.