Valid points Terry. The rear end has been a real struggle. I too am not a fan of the more vertical look. I like the sloping look of the Moke. That said, with the adjustable seats in the Moke and rear seat passengers, leaning the bar forward would put it quite close to rear passengers heads. This was one of the areas of compromise for me - loose some of that Moke flavour, but gain a little peace of mind. It will have a slight slope on the back but only about 3" over the height. At least from the rear it will have the Moke shape. As for fuel economy, we have one large trip we would like to do where this would be a concern, but most of the time it will be a fun run-about car for us so the economy isn't as big a concern.
The dash bar was my way of trying to tie the cage together across the front of the car. With standard Moke seats in their standard fixed position this bar would then be a bit close. With the Miata seats sitting a bit lower and farther back, our knees are well back from this bar.
Canadian Moke.