Watched both seasons. The acting was fine. The writing especially in Season 2 was beyond inane. I didn't enjoy Season 1 much either to be honest.
My advice: If after watching an episode or two you find yourself screaming at the TV "Why the hell is she doing that?" or "My God watching this is torture". Take my advice and watch a dozen or so "I Love Lucy" reruns or take a walk in the rain. 'Modus" doesn't get any better, there is no reward for perseverance.
Maybe people in Sweden act as Modus portrays them in real life, brain frost of something but you don't have watch. Also there are gloomy street scenes of Stockholm and plenty of running through tunnels in Season 2. I think those were in Season 1 too but I'm trying not to remember, if you're into that sort of thing.