Might be an unpopular opinion here... but look into the HP Envy series.
https://store.hp.com/us/en/mdp/laptops/envy-13-344514--1#!&tab=features
Metal body, 16GB Ram is an option, FHD or 4K screen is an option. Core i7 CPU as default, advertises 11 to 14 hours depending on use case.
My Envy...