I did not feel engaged to the plot. The dialogue felt abstract and kind of went over my head. Someone mentioned that the film is "very Russian" and perhaps that is part of it. I have extremely limited exposure to Russian culture but it feels quite introspective to me. I noticed the dialogue sounding a little like Putin, just sound-wise. Lots of "mmm" sounds which in my language people make when they are considering their next words. Somehow I see a connection there (that probably don't exist, if I am being rational)

You might try the Solaris novel instead. The movie was based on it, but as you know books can be very different.