I've had ideas for two, new, playable races:
InfernitesThese fiery creatures of destruction burn, eager for war. However, they are also very organised and wise, and understand the importance of superior defence as well as attack. They hunt in swarms, as there is a great strength in numbers.
+20% attack and defence
Unlockable Race Via mission chain (which I will think of if this idea is well received)
Unique profession: Demolisher.
Allows the player to decrease a planet's size by 1 for 200 energy every 60 hours. Will only be available if a) you own the planet and b) there is enough "free space" to lower it by one (you have to remove structures). If the planet is "Very Tiny", then using this ability will destroy it, removing it from everyone's databases and abandoning it.
Um, unless your getting rid of your tiny/very tiny planets I don't see the point.ErutansThis is a peace loving race, who are renowned for their distaste for war, but ferocious protection of their colonies. They are strongest when they are on solid ground, but have found a way to use their powers from afar.
Adds passive 10% bonus to planetary attack and defence.
Unlockable Race Via mission chain (which I will think of if this idea is well received)
Unique profession: Guardian
Allows you to DOUBLE a planet's defence for 12 hours, costs 100 energy, 36 hour cooldown. Also grants passive immunity to saboteurs on Gaia, oceanic, exotic and Terra planets.
Aha, I like this one. 
Any thoughts?