Below, I'll use examples from my current work in progress, Consorts of the Red King:
What I decided on:
Van hadn’t witnessed such vulnerability in Jorvik since their first night together, when he’d been accosted by the guard.
Their only advantage was in being thought dead, though that also presented disadvantages.
Being thought dead gave them an advantage, but also a disadvantage.
The little part inside of him that needed safe haven wanted to believe they were wrong, that the man they’d served for over ten years hadn’t betrayed them, hadn’t tried to kill them.
The little part inside of him needing safe haven wanted to believe they were wrong. Surely the man they'd served for over ten years hadn't betrayed them, hadn't tried to kill them.
Who'd spoken? Tayn? Jorvik? Both?
Let's face it, sometimes "that" is necessary, but team up an editor who shouts, "No 'that'!" and my OCD, and you get a perfect storm of find and replace. There are still many instances of "that" in the book, but not in every sentence.
I'm sure readers will thank me for that. Oops! There I do again!