I think it is the best time to invest in ether right now. The btc/eth ratio has been decreasing a little during the last two days, sitting around .093 at the time of writing. When ETH will start to rise again (1-2 months I think) it is likely to reach 0.15 btc. 2018 is the year of ETH with all the new ICO coming out and the new technical features will be released this year