I find it odd that people lump Armor, Starship Troopers, and The Forever War together. The only commonality between them is the use of powered armor; pretty much everything else is unrelated. Oh, I get that they might be responses to each other in some way, but everything from the style to the themes are just light years apart.
But if you enjoyed the movie on its stylistic grounds, please be my guest. I guess I just didn't find that ridiculously overdone style to be particularly engaging. (Now, give me a neo-noir piece and I won't be able to resist it.)
You can clearly see an evolution of his thinking (I would hesitate to say 'politics') throughout his books. He also has a pretty different take on things whether his books were aimed at a younger or adult audience. But even in the same general era of his writing, there's a pretty big diversity of social structures he explores. I don't think he chooses them randomly, no, but I also think he's trying ideas on for size rather than representing his actual views on a subject. By far the most common thread throughout his books is how he portrays women - often hypersexualized, often passive objects of admiration, and often subject to male gallantry that borders on fetishism. But the other themes are far more varied.As I understand it, he had a pretty radical political shift partway through his career.