Coastal Assault and Coastal Guard promotions both seem underpowered, particularly at first level of each. Perhaps give another 5% to both level one promotions?
Finally, one suggestion for a late game (transhuman or future era) promotion line. Given all the high tech and robotic units available, a natural area of military study would be the disruption and subversion of enemy information systems and technology. I think a promotion line that gives bonuses against robot, hi-tech, and nanite units would be very reasonable, and would help bring a bit of variety back to the late game combat. Perhaps calling it something like Digital Warfare or Cyber Knight, and made into a standard three level anti-unit tree much like Shock, Pinch, etc.