I assume, ethereum has some potential to grow big, but still, is it possible for any altcoin grow bigger than BTC? There are lots of promising projects out there...
Ethereum of any other coin, they are valued on the basis of bitcoins. I mean their worth in market is because of the bitcoins and hence they cannot eclipse bitcoins ever. I am not sure though that where the slow transactions take us, a lot of users lately adopted altcoins because of slow confirmations.