Balancing relevance and recency

Hello! ES newbie here. I'm trying to search a news site via headline, and trying to provide an illusion of sorting the results by published date, while maintaining the relevance. This is because people would like to see the more recent stories first.

I tried a gaussian decay (scale 1year, decay 0.75) and that brings up some recent stories, but not all. I tried multiple decays (1d, 7d, 30d, 90d, 180d, 360d all with decay 0.9) and it works great for terms in the headline, but if you search for an exact/partial headline, that doesn't show up on top.

How do you people handle balancing relevance and recency? What do you think of my approach?