Deathloop is great, I got it right around release and played through it over the course of a few weeks.

It doesn't take brainpower to solve. There's a whole time loop puzzle but the most disappointing aspect of the game was that it's a solved solution. The game spells out exactly what objectives to complete at which places and at what times. While you play through the game the first time you're uncovering twists and clues as to how to solve the puzzle but instead of letting you deduce a solution the games builds out a step by step list of markers for you to follow.

It's essentially the complete opposite of how The Outer Wilds, which has a similar time loop aspect with a puzzle to solve, handles it.

That being said, give Deathloop a shot because it's still a fun shooter with neat mechanics that lean very close to immersive sim levels of freedom.