I think it is interesting how Kickstarter is framing "successes" on that page as anything that has received funding. It fits in with the image they are trying to put forward as a funding site and not a preorder site, but is it the right thing to look at? A project that takes money and squanders it is a success in Kickstarter's mind, but I would guess most backers would disagree. To them the real success probably only occurs when the project's rewards are delivered. That rate is going to be lower than 43.84% and is probably more indicative of the long term viability of crowdfunding of this nature.
I think Kickstarter is amazing. However, it is considered a pre-order site by many. Which is incorrect. It is a way to put money towards ideas you want to see in the world. That is why they are known as "rewards" not products.
Stretch goals are easily one of the worst norms about crowdfunding sites. It's really hard not to do them, because it feels like you're turning down free money... but that's not what's happening.
The rise of small companies handling logistics on behalf of project owners after a successful funding, on the other hand, is a really great thing. I've experienced about 3 different companies (I'd have to dig through my email to get the actual names) and they've generally been competently handled. The more projects that take advantage of these, the better.
What I haven't seen (though that might just be me not looking) is project owners receiving good, professional advice about what to offer as rewards. Rewards need to be almost infinitely scalable and take into account snail-mail shipping costs and packaging time and effort, or you're effectively throwing away all the money you received.
Do you think a kickstarter-like site, but where backers become small owners of the company (instead of or in addition to ordering stuff) would be successful? Would it be legal under the JOBS act?
There's at least 100 idea people working on it right now - I guarantee it. We've heard from a few of them ourselves.
As for it being successful - it depends on so so so many factors. It's impossible to know for sure, but it definitely has potential. Angel.co seems to be handling this idea very well.