actualy everyone of us,have a different opinion about this of which  most  higher in year 2020 either bitcoin or etherium,but in my own thought,its hard to predict in this kind of situation,because of its volatility and unpredictabilty of its price value,but if we look up the coin market caps now,there is big chance that this ethereum would conquer the place of bitcoin as no one in ranking,because if you follow the spikes data chart now,etherium still maintain its consistent growing if you compare to bitcoin its still consecutively decreasing,so maybe in this situation we can say one day ethereum will surpass the bitcoin.