Blood_hit.ppd has a delay on the emitters yes, but that used to cause problems with emitters and got disabled in the latest update. It'll come back in the next update :)
And you are absolutely right about the wording on "Angle Mode", you suggestion is much, much better :D
EDIT: I forgot about the hidden UI! It's not documented anywhere yet, there's only right-click to change slider value, and Left Shift + Right Mouse to move all emitters at once.