If you want to limit attendance, doing it randomly is probably closest in line with the spirit of Burning Man because it doesn't target any particular group, but that hasn't worked so well either because it is going to end up keeping the large contributors at home this year.
I'm not saying this is absolutely wrong, but I need a better reason to believe it. Why is random decimation the thing most in the spirit of Burning Man? I get that we don't want to judge, wanted to be radically inclusive, so I understand why some of the other methods might be against that spirit. But I don't think being picked at random is in line with the spirit. The best I could argue is that it is less out of line than some of the others.
The lottery approach has the following result: The playa is populated by a mix of the randomly chosen and the wealthy, and the extra value is captured either by the lucky or by deliberate speculators, instead of being captured by the community. And while the Borg is not the community, if they do their job with the right spirit, if they capture the value then some of it trickles down into the community, in that they have more to spend on playa services or can make tickets cheaper for others.
No matter what you do in a sold-out event with transferable tickets, wealth is going to be the biggest factor in determining who gets the scarce tickets. You can't stop that. The most you can do is control who it is that receives the surplus price that the wealthy are willing to pay. It's either going to be the lottery winning burners, the speculators (who won or who buy tickets from suckers who sell them at face value to speculators) or the org.
Which is most in the spirit of the event?