I predicted last year, here and here that starting Feb of this year until Feb 2019 we would be in a bear market.
Using the same techniques, I think we could see sideways trading by early next year and even some significant spikes in price, but whatever spikes in price that come in 2019 will be vastly overshadowed by what starts to happen around the summer of 2020. I think the market will top off sometime in early 2021. If the technology is finally ready for mass adoption next time (without a scaling debate) then the price will continue to climb into the middle 2020's, but if not, another bear market will start around 2022 and last until 2024. This pattern will continue to repeat until mass adoption of crypto is achieved.
Good calls! And you may be right, it will be interesting to see if bitcoin is still king at that point.
Next Bitcoin block reward halving will be around May, 2020. Therefore, it is safe to say next At The High (ATH) will be around summer 2020. Can it happen it before? Why not, time scale is getting small as @jrcornel observed more attention, more people, more capital, more wildcards (ETFs).
There could be new ATH's well above where we were last December sometime in 2019, but it will be nothing compared to what the price will be in the latter half of 2020. I think that the climate we saw start in spring 2017 in crypto will return summer of 2020 and fall of 2020 will be very similar to what happened to bitcoin after the split from BCH. Not sure though if it will be bitcoin, or some other crypto coming along to replace it as king.