One of these days, I'm going to hire some programmers (as opposed to deprogrammers) and have them teach me how to do stuff like this. It looks like more regulars have plus ratings rather than minus ratings. I figured that it might be the opposite.

I haven't seen a recent post for this but really should have - it would have likely garnered a fair amount of attention on a week short of actual baseball news, but...
Sean Smith and Jeff Sackmann now have this data for the minor league level up on minorleaguesplits.com. Here's Sean's recent summary bit on it from the Hardball Times.
(Very, very) Initially, I'm not super keen on these results - they don't look as stable (y-t-y) or as consistent w/ the scouty consensus as I'd like, but Sean's covers this stuff pretty well in his aforementioned piece.

Well, there are lots of questions. The OF, for instance ought to be closer (I'd think). And where did he get the run values?