It's my personal opinion that battle logs are the superior raw data set (assuming we can get them to contain a teeny tiny bit more information). With any kind of plugin, we can only analyze the data that the programmer of the plugin thought to include. With a full battle log, there's really no limit to what we can do.
For example, who would be interested in seeing a "sweeper score," that is, the average number of kills a pokemon gets per match it appears in? Similarly, what about a score of percent of times KOed in a battle?
We could also get data for the most frequent switches into any given pokemon or most frequent replacements for a given pokemon (as in, you switch out x--or x faints--and you switch in y).
A proper battle log will let you analyze anything you want, rather than just anything you thought of before the battle. They also provide a sort of "paper trail," in case anything needs to be re-counted or verified.
The downside is, of course, the huge size of the datasets. But disk space is cheap these days, and I really don't think that should stop us from keeping and utilizing them.
Of course, this is all a conversation for another day.