I don't agree with your level 16 talent as you should be doing fine with your "E" already and Prescience. If you see them trying to gank you and you have prescience off CD, "E" out and take a sip of the well. If you don't have enough health tell your team not to team fight and go back for health, and you should be ready for the next team fight. Also, Second strike is very valuable for zoning the enemies out.