Today and a few weeks I will not suggest to buy, just wait a little, when the halving of bitcoin will be near there will be much less people in the other coins and everyone will be busy to buy bitcoin, so at that time Ethereum will reach to much less amount. Just see the near future will be about $1 per ethereum.
You don't subscribe to the theory, BTC rising will cause all boats, to rise to some degree as well?
not necessarily.
there is no rule about this. sometimes some of the altcoins have moved with bitcoin price movement and sometimes they didn't.
one of these coins were always LTC that moved with bitcoin.
but i think if the BTC price rises that will cause a lot of ETH investors to dump their coins in order to be able to buy bitcoin and not fall behind on the train.