To become rich, you need people below you to buy into the system.
You're absolutely right, but
only if making USD were the reason for the system to exist. Again, I feel you're looking at this from the perspective of "how can I make money from this?," instead of, "why should I use BTC in the first place?" To touch on your third point, this is exactly the reason why we are seeing such high volatility of value -there are far too many "investors" with that mindset. After hearing any given news broadcast, the average person is not walking away thinking about the core fundamentals of Bitcoin and its potential, but rather the capacity for financial gain (or the missed opportunity had they bought when they first heard about it) and always in the context of USD.
1) Widespread adoption by a critical mass of people before it can become worth anything.
This isn't the case at all. As long as one that is willing to give it up in exchange with another that is willing to accept it, whether it is a niche market of 5 people, or 5 billion people, actual market size does not necessarily matter as it operates within the confines of that one exclusively mutual and direct relationship. To be clear, demand and fungibility still have an impact on the value, but it doesn't require adoption on a global scale -even if it only exists within a small closed loop market, it still retains some level of worth (the online drug trade could be considered such a market). The only time actual mass of quantity consumption matters, and aggressive marketing is needed in these cases, are for pump & dump trends. The challenge being, we can't exactly know for a certainty which is such a scheme until it is too late ..of course, research and some common sense can help one avoid them.
if I own a large amount of any alt coin, it is in my interest to have as many other people I know adopt the coin.
Yes, of course it would be in your special interest for that to happen, but because it shares that characteristic of a pyramid scheme doesn't mean that it must be one. If I hold 100 shares of Google, it is in my interest for many others then to buy up more Google stock and increase the value of my own assets.
On the topic of mining, it was never meant to be the manner of acquisition for most people. It was simply a means of both distributing the coin into the market by a commitment of 'work' and securing the network. In any scenario, be it financial or any other opportunistic situation, some will have a privileged path while others will not. #factsoflife. But you are also calling out the people who have risked the most ..should they not have a proportionally greater reward? The use of computational power to both mint coins and secure the network is rather clever as the cryptography the protocol is built upon can't be feigned, it is un-biased, verifiable and fair.
The crazy volatility that we are seeing will continue so long as the market remains predominately saturated with speculators. This will not continue, however, as merchants begin accepting cryptocurrencies and their use becomes a means of trade for goods and services as opposed to taking profits in USD. At this time the price of BTC, or more importantly, the purchasing power of it will then be dictated within the free market. That is why merchants ought to be the primary focus of crypto gospel efforts more than other 'investors'.