You say Exclipse would be an instant win in a space battle because of it's super laser. I'm not sure how thats different than the Death Star II's super laser, I think it recharges faster even.
Anyways I think both should be buildable but take a long time to construct. The FoC is already over-powered even with the recent update, one eclipse would help. Also, they need to change the Death Star II - IG-88 scenario. I was at Bothuwui with my death star and right after going in GC view after the battle, Bothuwui blows up and with it the Executor, Palp, etc... Then you can't rebuild the Second Death Star, wonderful. I would be ok if the price rose and there was a timer, but at least let us rebuild it.
On top of all of that, the AI in this game SUCKS. units sometimes go off chasing enemies, Auto Resolve is horrible. One battle I had Darth, Palp, Thrawn, and a couple Star Destroyers. I put them in a battle with a lvl 3 space stations and 2 Venerators...everyone died and none of the enemy did. I realize you should fight battles but if the AI is gonna be biased as to who wins then what's the point in auto resolve.
Anyways, sorry for going off in a rant.