I think that the major hurdle here is still in terms of trust.
The fact that you're funding someone internationally, who you may have never heard of before, while taking a huge counter party risk whenever you send funds through a irreversible payment method that cannot be recovered if the other party goes rogue means that people tend to be more cautious, and credit/investments thus becomes scarce.
This may be less of an issue nowadays with a lot of projects being more transparent with the team and all that, but that doesn't lessen the fact that there are still plenty of rogue projects that use fake team profiles etc. to raise funds. The fact that international legal recourse is difficult also sort of limits the sovereignty of what investors can do. But at the end of the day, the benefits of raising funds through BTC compared to traditional IPOs are obvious, and these hurdles I think are only a matter of time before they are overcome.
In addition to that there are other things which are influential to the market. Any single major player or group could change the direction of market at will. Recent upward surge in bitcoin and many alt-coin is proof. Thus some investor may find it lucrative with highest possible risk.
That is already a given fact, influential or what we can market manipulators, whales will also be in the picture no matter what. As you have said, some entity from behind trying to stir the market and pushed the price by $1000 in matter of minutes. That's how big those people are. But regarding your original question, I would agree that volatility and then trust could be one major obstacles. Volatility because you don't know if the project could be a success or if your money will give you good returns. And then there is the (pseudo)-anonymous nature of Bitcoin, are you willing to throw money on some project wherein the people behind are not transparent?