As someone who went with the 52 some advice? Don't make the rear even crazier. When you have battery the 52 -- for me at least on the Aventure-- is a way better ride but if you accidentally run flat (I got lost one day in unfamiliar back-roads) you are asking to kill yourself trying to get the thing home, even in first.
It's bad enough that you're hauling an extra 30-40 pounds over a normal bike, without the drag of the rear motor making it feel more like around a hundred. By the time I ran it completely flat I was only about a mile from home, but that was a long hard mile. Felt like I was going uphill even on some declines.
Just something to consider.