Honestly, a decent derivatives exchange would really help. Whales could have sold covered calls to provide liquidity without outright selling.
With Bitcoin's volatility, leveraged derivatives would really not be necessary to make money.
That's if you're using derivatives for leverage. You could just as easily use them to hedge your position without selling. I'm talking about using BTC as a financial tool, which requires stability, not as a trading instrument.
If there is any kind of exchange for derivatives people are gong to speculate, that is simply how the markets naturally work. If you attempt to prevent speculation then the market will not be efficient.