Ok, so having driven a reverse trike just a little, I can say you guys missed one point. The Elio has a very narrow butt.Will sitting in the "center" , and not left of center, make passing more difficult in an Elio?
This means you can run tighter into corners and cutoff quicker in passing, or have more safety clearance.
So yes, sort of.. Sitting in the center gave you that more narrow rear and duplicate clearance on each side.
You can also have a better sense of presence sitting in the center or gravity and that may help your sense of space.
Admittedly you'll be more off from the driver side to judge distance down a line, but you see that side more clearly than a 4 wheeler.
(as usual for me, possibly too much information)