Presumably one could build a haka with a motor mount on it.
In fact one for each side then you could go water ski-ing as well!
Seriously though I have gone for the evolve. We all know hobie for the quality products although in my mind they key to all this is the battery technology.
I am glad that you like the Evolve--I certainly would prefer a Hobie product if there was one which met the need. My main concern about the Evolve is that you would need either to give up one of the Mirage drives or have to change from a Mirage drive to the motor out in the water--where it is sometimes pretty rough where we are. A side mount or a rear mount behind the rudder sounds like a good way to have access to both the motor and both drives.
Please let me know how this works out for you and for other Evolve users.
i use the evolve on the revo with a rudder mount and on the ti in the front mirage mount swapping the evolve for the mirage when you want to and keeping the other (tethered) on the tramps.
Control for the motor is in the rear so you can peddle and motor at the same time. Clearly with an Ai you have to swap over.
There are other torqueedo motors that mount just like outboards so you dont have to stick with the hobie version. some have the battery on the top so are one self contained unit.
May the odds be ever in your favor..