I don't think is it good to buy bitcoin this coming 2019 but since you give some tips it might be worth it to buy bitcoin this coming 2019.
Honestly, I just following the movement price last 2014 and 2015 so, 3rd quarter of 2019 I'm sure that bitcoin price will rise up again just like what happened last 2015 and I think more event will come this coming a year.
2014/15 crash took about less than 1 year of decline in BTC price before the recovery started. I believe if BTC were to reach new lows now that we would actually be in a bearish market for longer than that time.
2014/15 crash and today crash are different, back then there were only a handful people involved while right now almost everybody knows about it and some countries were starting to accept it. And IF we are going to create a new low in the future, I am afraid there will be no more new ATH in the future because of its volatility.
let's talk about Japan, for example. They were regulating their exchange and basically, they were supporting Bitcoin on that country. And when the price goes this lower, do you think only a handful people that lose their money? no, it's a lot.
and of course, they will suffer a set back(mentality and financially) if the price keeps moving down and creating its new low in the future. I am afraid, nothing good will happen.
Yes they're different but they're not worlds apart. The actual event that caused the crash in 2014 was far more cataclysmic than this bubble bursting but the market still recovered from there. While you're right that adoption is much higher this time around, as is awareness, it's still a long-shot from its true potential. For every 1 person that got burned this time around there will be another 10 or more looking to invest in the next bull run. Long term bitcoin cannot sustain such harsh highs and lows but it will survive this one.