I'd actually say that is close to an optimal traffic circle. I'd add an even inner-er-er lane, make the outside lane a mandatory exit. If you enter in the right lane, you exit. The middle lane connects to the left of each entrance, and is able to exit at ANY of the exits, and the most inner-er lane would allow you to potentially bypass a traffic jam at another exit.
In which case I agree completely. And, from what I can tell, they're about the same size, so IMO this was a design miss, not a space constraint.
For me, it's all about the surprise factor. In my example, the outer lane almost goes all the way around. So you end up surprised after passing two exits and then being forced to merge to pass the next one. GGP's example is completely symmetrical, so nothing is surprising.
Yeah, that outer lane thing is weird, you should always be able to circle the roundabout (although you should be going on the inner lane, unless you know you're exiting next).
