Overall, I did enjoy Cyteen for the story and the characters, particularly in the development of the second Ariane. However, much of the politics and the verbal sparring went over my head, and I fear this was a significant portion of the novel. All of the different alliances and enmities between the major political influences in the novel seemed to change so fast, and often to cues that I as a reader did not pick up for several pages after.
Of the many interesting things that Heinlein addresses in Starship Troopers, the thing that captures my attention the most is his discussion of power, both its origins and the ultimate responsibility which comes along with it. As American voters have, over the last fifty years, become less and less engaged in the political discourse and more dissociated from the violence (or threat thereof) from which their political power is derived, Heinlein's views on this have become even more pertinent, not less.
I have to say, no matter how much I love Heinlein, every time he takes a break from storytelling to shout from a soapbox about his particular political theory, I really want to throw something at him.
So a couple thoughts on Heinlein. First of all, although I agree with the below comment that alien races can imply racial connotations, I think that in this case Heinlein used the communal properties of an insectoid race to demonstrate the potential power of a communist social structure in a species adapted to it--and to show it's fundamental incompatibility with human drives. Second, I think Heinlein's discussion of the source of political power, though not directly involving race or gender as a major factor, is a potentially useful tool for understanding modern political power relations.