Thanks for your comments, Greg.
You have correctly identified some of the gross oversimplifications of the chart.
My "(pre-Masoretic) Hebrew Texts" is meant to cover that amalgam of texts that include proto-Masoretic as well as all the other flavors that get filtered down into the SamPent, DSS, and LXX. (That's why I use "textS" instead of "text.") As you note, there are all sorts of strands of which the proto-Masoretic is only one. So, rather than a fixed bar, I should probably use some kind of ragged edge shape to indicate the uncertain and composite nature of this groupings of texts.
My "Hebrew Original" was meant to indicate that somewhere in the hoary past, there was some kind of original autograph, and my chart does not try to define how they eventually end up in the "pre-Masoretic" pile of texts nor how they may have been edited.
My "Greek Original" was an attempt to acknowledge that some books of the LXX were originally written in Greek (2Macc?, WisSol, Esther additions, etc.) Same deal for the "Aramaic Original." (Daniel sections and parts fo Apocrypha?)
So with your comments in mind, I've updated the charts, and hopefully they are a bit more precise.