WOW!!! that is a serious amount of air
Maybe making a new head for the valve altogether and moving the check back slightly would allow for a bit more per stroke?
I do the do same thing while making/drawing things up, get half way through something, and start thinking "Oh, I'll need that too" or "I should make three versions of this and see what difference they make"
The on-board reservoir sounds pretty awesome as well, ill be watching it unfold closely