A lot of these suggestions are for competitive, which is fine, but I'm not too big of a fan of it. For co-op, I'm a big fan of both Insurgency and as WindKnight suggested, Warframe.
PlayerUnknown's Battlegrounds is really new, and omega-jank, but its probably the most strategic shooter I've played in 10 years, and a lot of fun with a buddy.
PlayerUnknown's Battlegrounds is really new, and omega-jank, but its probably the most strategic shooter I've played in 10 years, and a lot of fun with a buddy.