Everybody is talking about ETFs, but I don't believe that they will be the fuel for the next price rise. As Bitcoin moves further towards being a store of wealth, and merchant adoption increases as secondary services like the lightning network stabilise, they seem more likely to trigger the increase in value. The price of Bitcoin seems to be cyclic, and to add a zero to the price every two years. I think we have missed the chance in the current cycle, but the one due in the summer of next year looks to be on target. Will the current enhancements arrive in time to fuel the next parabolic price increase?
Neither ETF nor lightening network will help in increase the price in longer term. However, if you really want to see long term and stable growth, merchant adoption is the key!
Majority of the ETFs that were proposed to SEC were synthetic in nature. The only exception is Winklevoss ETF. Synthetic means no physical bitcoins will be purchased and stored, so no impact on the market. Winklevoss is still under consideration but I don't see much hope there.
LN is a technical upgradation of the network. Think logically, if there is no place to use your money, what will you do even with a billion dollars in your wallet? So LN is most likely not impact the price for long. A short impact will be there but that will not last long.
The only key to growth is merchant adoption. When bitcoin can be used directly for purchasing goods and services, people will realize the value of it. Otherwise it will just remain an underground currency and everytime you want to realize its value, an exchange to fiat will be needed. The change has already started but expanding at a very slow rate. It will take time, but will happen eventually. The day we will be able to buy our daily goods with bitcoin, we won't have to look back!