I don't believe there's a better system out there than the one we've currently got. Which is free markets with mixed ownership of resources, but most of that ownership being capitalist. And anyone who argues against it needs to come up with something better which is actually workable.
You can of course play around with the ownership model a bit i.e. more cooperatives, certain sectors of the economy being state-owned, so you're not totally stuck with capitalism.
But that basically leaves us in the situation that we're always going to be patching capitalism and cleaning up its messes. But that's OK, because the same would be true of any economic system we use - governments are just as good at fucking up as greedy CEOs / casino capitalists / shareholders / bankers / [insert personal demonology of choice].
There is unlikely to be any perfect system.
Free markets work better to distribute scarce resources than any other system we've tried. However, only if they're regulated. You can't have a free market without property rights for example, and that means law, which means government. You also can't have a proper free market if people can pollute, pushing the costs onto somebody else and taking all the profits. That's called externalities - and is another place where government regulation is the best solution.
But as to alternatives, we're a bit short of them. Hence we're likely to still be patching free market capitalism 100 years from now. And maybe still getting people complaining about neo-liberalism too? Or maybe it'll be post-neo-liberalism by then...