Woot. Now: nitpick mode!
* The Eclipse should only be able to destroy target land if it attacks and is not blocked, IMHO.
* For the "destroy creature" ability, a Rangestrike ability might be apropos for the Eclipse (tap to deal adamage to target attacking or blocking creature) rather than the ability to target any creature, or alternatively some kind of Firebreathing variant (probably with black mana). Also, it should not be able to target creatures with Insignificance. Can't have it selectively zapping characters, now...
* The Tie Bomber should only be able to bomb if it is attacking (after all it should be possible to shoot them down): here too a Firebreathing type ability might be in order, probably with a limit to +1/+0, or something.
* Why use green mana for the Dreadnaught's regen ability?
* The "imperial" class should be "imperator" class.
At least according to Dr Saxton. Technically, they are all "imperial".
* The Acclamator should be able to take over any type of land if it attacks and is not blocked. Otherwise, it would be impossible to conquer all the planets I've posted.