1. Bitcoin will still be king
2. More institutions will join the fray
3. Regulators also ready to jump in
4. Volatility will still be synonymous

Its getting expensive because supply demand, and because it has limited supply. and the fact that demand continues to rise.

In the future just about all of us.  It may or may not be known as Bitcoin.  We will not even think about it as compensation will move as freely as communication.

The reason is simple: traditional payment systems can not do this effectively

i can say mining is good if you are w. so many fraud and scam site are available and daily many site are closing their business due to government regulation.

select that site which one is older and paying regularly.

Impossible to say. Could go to zero.

With much of the world heading into Christmas and New Years holidays, trading will be light. Holidays have often been times prices dropped lower, so it may have some downside yet.

Bitcoin Cash has been quite negatively correlated with Bitcoin. That is to say if you keep an eye on things the price of BTC+BCH stays much more constant. When one goes up, the other drifts lower. Best to buy and hold BCH along with BTC for that reason alone.

Do you already have an idea what the concept will be like?

How much CPU time is needed to mine 1 bitcoin?

is your website just for chat?