It's pretty hard to be free of tropes in this day and age with so many narrative avenues, elements, structures already explored. I'd argue that Andor may not reach the heights of the best prestige dramas, but it's in a fairly high tier in its own right and certainly more mature in it's storytelling than the rest of the Star Wars catalogue. I don't want to say it's disingenuous to reduce the show's strengths to "it's dark and gritty."
Its not a flawless show by any means but if we're talking about simplicity/complexity of a narrative, script, and plot structure, Andor is on a much higher level compared to the rest of the filmography.
Andor had nothing to do with the Death Star plans aside from the implication that the prison arc showed prisoners working on Death Star construction components. I think you're confusing titles and look to be working from Rogue One there.
No I didn't leave the first movie off the list. From an objective standpoint, not from a movie that is beloved by me standpoint, it's an incredibly simple premise marked with a very basic script, and is heavily derivative of prior works. You want to talk about how Andor or Rouge One is plug and play right after backing a film that is, at its bones, a repainted and repurposed Kurosawa imitation?
I love A New Hope and maintain that it's a time tested and enduring hero's journey (and my second favorite work in the Star Wars anthology behind Empire) but there's nothing particularly remarkable, deep, or complex about the script or the narrative.
As to the last paragraph, mileage varies there. Personally I think the casting is a mixed bag. Thrawn (so far) and Baylan being terrific. Elsbeth, Ashoka, Huyang, Mon Mothma, Anakin (voice acting counts) good to fine depending on the episode. Sabine, Ezra, Hera, Jacen, and Baylan's apprentice are fine for my taste. The only character that I see that has notably poor acting is that x-wing pilot that's shown up in multiple Disney+ shows. I don't know whose buddy that is but he's not a good actor. The script is nothing special, but not it's better than Book of Boba Fett, Mando S3, and Obi Wan. The pacing is not perfect but I haven't seen anything truly egregious.