As you can imagine with a thread as long as this one much of the points you make have been made before but there are some in here which I surprised have (to my knowledge never been made).
Telegraphing the Emperor's trap adds suspense because we know that the Emperor has something up his sleeve but the Rebels don't so when they arrive we aren't just thinking will they survive the battle we know that there is added peril and out heroes are charging straight at it.
It's the same with the Boba Fett double deal scenerio, you can either get a dum, dum, darrrr moment of suddenly revealing a shock plot twist or you can extend the sensation over a long period of time by letting the audience in on danger that the characters on screen don't know about.
If you chuck in the added surprise of Luke being on a second Death Star (not the one he and we are lead to believe the only one) we then get the best of both worlds because we have the suspense of knowing the Emperor is pulling the wool over the Rebels eyes but also the surprise that the films it pulling it over ours.
Sudden promotions aside (I don't have the same beef with Lando that some people do he was over a barrel in ESB and had a city full of people to think about before his friends) but would he be a Commodore instead of a General or maybe a Squadron Leader?
Space Opera is a real hassle when it comes to military ranks, is space land, sea or air?
Solo should be a Commander.
Most of your other comments have been addressed elsewhere in some shape or form but if it's worth saying once it's worth saying again.