I don't think it's the right structure. I like the idea of open allocation (which is more defined) in a decent company better (although that, too, is rare). Paying typical young people to "do whatever" is not going to lead to the kind of performance that would sustain the fund. Also, I love the idea, but I feel like a lot of the best people are going to still go to YC. There isn't really room for more than one YC, because (like academia, which is all about reputation) most incubators are a reputation drag.
Also, I think "startups" generally suck. By startups, I mean companies built to become billion-dollar concerns (and willing to throw culture and people under the bus to get there). I'm starting to think of that as raving narcissism. People should want to do great work without that instant gratification and entitlement of Big Exitzzzzlol!!!!111
A better idea is this: http://michaelochurch.wordpress.com/2013/05/07/fixing-employ... . The idea is that people sell call options on their time, as a consultant. Let's say my fair market value is $200/hour now. I might sell a call option, struck at $150/hour, exercisable within 5 years. That's probably worth $100-150 because I'll be more skilled in the future. It lets people finance their career needs early, but it also makes the consulting market astronomically more efficient because the option-holders (who would tend to buy underpriced options) have an economic incentive to find work for talented people.