I think the game got quite better now with the Emperor Edition but I share Cruzz's opinion.
I'd say it's worth buying it now especially if you are up to play it modded.
I tried for quite a while this mod:
http://www.twcenter.net/forums/showthread.php?630814-Divide-et-Impera-%28Divide-amp-Rule%29-Main-Thread
With that mod everything is in general much better, from graphics to performance to AI (much better) and combat system. At the highest difficoulties the AI is very aggressive and the game gets pretty damn hard.
Worth playing it at least once to see the difference!
That said, the new basic Rome 2 is still way better than the one released in september