The game would be in a Warcraft/AOE/ Stracraft fashion.

My three candidates are: IX, XII and Tactics.

For the first, it would be pretty awesome to battle it out between Alexandria and Lindblum. There would be airship battles, summons, ground warfare, you name it. 

For FFXII, you would have Dalmasca, Arcadia and Rozarria killing each other. Awesome air battles, and very cool ground warfare are ensured. 

Finally, Tactics RTS could see the Hokuten and Nanten killing each other. With very medieval like battles. 

Personally, I will vote for FFXII, as I would enjoy seeing the Rozarrian war machine in an all out war with the cool Archadian army. 

RTS sequel like Revenant Wings?

XII, because of awesome airship battles that should have been in the game in the first place!

FF 13, because knowing SE, we would never live long enough to see that atrocity made

damnit, I misread the title. I thought it was which game would you like to see get a remake since the title got cut off. -_-

what is RTS?

VI because of the mechs!

Real time strategy.