i think if you want to sell all your ADA to buy ETH that is a correct idea.
ETH is much more stronger and have a clear growth, and in this time i believe if ETH will hit at least 500$.
ethereum is stronger than ada, thats right
but its better to split our money in this crypto investments,
so, buying ethereum and ada will be a better idea rather than if we have only ethereum in our bag,,
"do not put your eggs in one basket"