I am very sure that etheruem will not top BTC now or in the future. The level of ETH fluctuations this days is very worrisome, and the worst is that it does not recover after much droping in it prices, unlike Bitcoin, the probability of it's recovery is higher. To think that ETH will be the next generation coin/token is just not realistic at all.
One thing to note here is that ETH has many serious competitors, in the like of EOS and NEO, these coins has tremendous smart contract and the Dapp technology war with ETH. I think that the era of ETH dominance in this regard ( smart contract & Dapp) may soon be a thing of the past.