I do not think that it would be a good idea to sell all your bitcoins and buy ethereum. Although ethereum has always been and is a good investment, it is not worthwhile to shift all funds into one coin in any case. Bitcoin is not so hopeless, it slowly eliminates its shortcomings and is restored. It's just not yet known how quickly it can recover in its former value and how fast it will grow in the future. Now you need to hold both bitcoin, ethereum and other promising coins.