I like vests, but it's easy to look like a doofus in them.
I do not personally want to look like I've been transported into the current day from 18-dickety-three.
For that reason I generally stay clear of what could be called waistcoasts...
Moving towards darker colors (browns, navy) that either work as a middle layer or are bulky enough to be an outer layer, matched with henleys, boots and denim.

Steven Alan hiking vest

Spellbound reversible (tan/olive) nautical style vest

Spellbound hooded tweed vest