C&C:A is a great game. It is everything that I expected the film 300 to be, as far as immersion into the ancient world. The only "problem" is component quality. I actually find myself getting it out less frequently because the board is a pain to set up. Obviously the mounted board for expansion 2 or 3 would help this.
It seems silly and whiny, but the board keeps this game from being played more often. I don't have a problem with Pax Romana's unmounted board. Maybe that's because Pax is a longer game. For the length of gameplay I get from C&C:A, set-up is a drag.
Also I should note that I prefer strategy to tactics (C&C:A focuses on tactics of ancient warfare while Pax is a grand strategic game). The best games find a good balance between strategy and tactics. I realize other people like tactics more than me, and I'm glad when there is a game that pleases both the tactically and the strategically minded gamers.
That balance occurs in Pax's "short" scenario. Playing in 2-3 hours, there isn't enough time for centuries long strategic planning to overwhelm tactics, but there is still strategy (note: don't abandon the Italian peninsula to fight barbarians if the Greeks aren't busy fighting someone else).
The funny thing is that both Pax and C&C:A have "expansions" to fix them. Oh well. I guess that's why game collecting is a hobby.