I haven't read either Imbalance or Demons of Air and Darkness. So, the Jarada are developed in those stories are just used as stock heavies? In any event, I would like to see more development and focus on those aliens.
Same with the Tzenkethi (I know a novel's coming up to address them), the Talarians, and the Nausicaans. Has anyone proposed a Worlds of TNG type series? Because TNG introduced a lot of interesting aliens (Talarians, Nausicaans, Anticans, Ktarians, Selay, Jarada, etc.)
More things I would like to see:
-Lysians/Satarrans
-Silent Enemy aliens
-Schism aliens
-the ship from Dead Stop
-Vulcan Isolationist Movement
-Ba'el (sp), the half-Klingon/Romulan young woman ("Birthright"); I thought she and Worf had a nice chemistry and would like to know what happened to her
-Toral
-Kurn's children, Kurn's spouse (are they members of the House of Martok too?)
-Geordi in a romantic relationship
-Wesley's reaction to the Picard/Crusher romance
-Aligar-like to see this race explored more
-Carreon-ditto