Can't really help with the pony but If you make horsey sounds when your riding, it's close:)
The left and right side are mechanically linked so the both have to move in unison, no flopping... it's the link that makes the arrangement stable during the transition.
The production model can have any bar end you want, ski pole bend, road bike horns or straights. I hear you on the risers, we are doing just that.
If you are in aero and take one arm off the pads (ex. to grab a behind-the-saddle bottle) what happens to that extension (i.e. does it flop around)?
Love the bars from a design standpoint. Two improvements I'd recommend are a lower pad stack (you can always add spacers), and the ability for more pad fore/aft adjustment. An option for upturned ends (mini ski bend) would be nice for both the basebar and aero positions. Oh, and I want a pony ;).