People think that money making is quite a very easy task using bitcoin. This is not true, it has got the same difficulties as well the increased competence to be successful. So if the investment is expected to grow slowly then in a secured manner it'll grow. Else we cannot predict the outcome as we need to be lucky to grow it in a short.
The best way to invest in Bitcoins right now is BTC trading, I mean buying and selling bitcoins. forget about the mining bitcoins and keeping bitcoins as an asset for now... If you really want to make serious profit with bitcoins is through buying and selling... With your $250k you can double your initial capital in few months.
We don't need startups and new projects. As this guy said, bitcoin and altcoin trading would make the initial capital 2x or 3x at least.