Yeah, I think #1 is virtually impossible, but still could happen in the event of a major international collapse of the current financial system. Unlikely, but possible.

I agree that #2 is the most likely short to mid-term path (less than 3 years). Bitcoin mining is currently quite profitable and it is not as hard as it used to be to acquire mining hardware. Right now, an Antminer S9 can be bought for about $1500 USD and will mine about $400 per month worth of Bitcoin, creating ROI in about 4 months. This will cause the network to grow. With the next block halving not till about 2020 or so, and the market showing resilience in the face of attempts of governments and banks to trash it and stamp it out, moreover the price being at record highs and it becoming much preferred as a way to transfer funds internationally vs. Western Union and MoneyGram in may places, and with Japan making it fully legal and accepted, I think Bitcoin has a bright future. The upcoming hard fork is likely to produce gains for holders, so I think that is part of what is continuing to drive the price up, but there are many other factors and despite the record highs, I think there is still far more upside potential than downside for Bitcoin in particular at this time. Still, anyone investing in mining hardware should diversify to some degree and not just buy Bitcoin mining hardware, but should diversify into Ethereum and Litecoin and Dash hardware. Buying and holding Bitcoin is still a good, simple strategy to ride the wave, I think. You just don't want to buy more than you can afford to lose and not cause yourself any serious distress.

But I believe that #3 is mostly likely to happen in the long term (3+ years), considering that Bitcoin is facing major scaling problems and has no other use than a store of value or money transfer method. I think we may well see much larger gains for Ethereum and especially Ethereum-driven application tokens, such as Aragon, Augur, Golem and SALT. All the Ethereum ICO madness is just getting started! But one should keep in mind that all these Ethereum-driven applications and tokens require you to spend Ethereum to really make the best use of them, so this means that each one that succeeds will create a greater demand for Ethereum. The big issue is that these blockchain applications are mostly in Alpha and are for the most part essentially useless at the moment.

And that's why Steem is so great! You can actually USE your coins for something! Woohoo!