I use to rent Scrypt miners sometimes. In Jan 2014, the cost of rental was around 0.02 BTC Price/Mh/day, today the cost is only 0.0075 BTC Price/Mh/day (
http://www.betarigs.com/) .. and numerous rigs are available now. Back then Scrypt Rig owner's were able to recover the cost of investment in 3 months time, but with present scenario..maybe it would take atleast 8 or more months.
People always say Wall Street, Hedge fund group entering btc scene, but as like most of them I am losing hope. With BTC at ~$600, all those wall street, hedge should have entered and price spiked again.. I lost quite a money on betting alt-coins. Accepting it and trying to recover.
With BTC malleability issue and numerous security issues/hacks going on, ..I do not have a good feel about BTC's future.
Crypto concept is cool, but BTC and alt-coins are like... you printing your own notes and asking people to believe in magic and value. I hope Govt's will look for a way to digitize fiat. Just my opinion.