Tarkovsky's worst movie

I liked 'Andrei Rublev,' 'Nostalgia,' and 'Mirror.' Those films were like visual paintings, and even though they lacked traditional storytelling and plot, Tarkovsky's style and artistry is evident in all three. Here are my main issues with Solaris.

1) Why did Tarkovsky choose to make a film based on some hackneyed science fiction crap? His other films I saw were surreal explorations of human spirituality. Here I feel like I'm watching some terrible soap opera based in space.

2) The acting was AWFUL! Russian is my first language, I was born in the Soviet Union, and I remember watching movies around the same time period which had actors that were almost aware that they were acting while the camera was rolling. How did Tarkovsky get such incredible performances from his actresses in films like 'Nostalgia' and 'Mirror,' but here everyone sounds so forced and self-aware?

3) The visuals were hindered by the effects, which look terrible today. 'Andrei Rublev' is like a moving painting. The scenes in 'Mirror' are delicately crafted like a naturalistic painting. Here, I thought there were some beautiful shots in the first ten minutes, but everything onboard the spaceship looked like an unaired episode of 'Star Trek.'

Feel free to disagree with me and talk about the movie's amazing philosophy, which I probably didn't care to understand because I couldn't take any facet of the story seriously in the first place.