From a UI perspective, the research interface could use some simple tweaks:
a) Display the number of research centers (military/civilian) that you have somewhere on the screen.

The research icon at the top of the main screen flashes/lights up if you're currently researching something... An icon flashing is supposed to draw your attention to it (e.g. a problem), it shouldn't be an "all's well" indicator. (unless the other icons are also lit when 'alls well').
c) There's something funky with how things are lit/unlit on the research trees. I'm not sure what it is, but it really annoys the hell out of me. Ideally I want to clearly see the difference between:
- things I have bought, and fully upgraded
- things I can buy/upgrade
- things I have the prerequisites to buy, but can't currently afford'
- things that I don't have the prerequisites for
It would also be good as you suggest to display a research queue (personally I didn't realize all of the research trees went into the same queue for a long time - a visible queue would clear that up).