Best place for your cavs and phracts is in your compact defense city. If you have no range setters other than ATs, and somebody like intertron were to send a warrior bomb to eat the cavs, you would be laughing and he would be VERY confused, as the warriors would be shot down by your archers long before they even get close enough for your cavs to touch them. An ineffective attack like this would yield you 0 losses. The same would happen if the attacker tried to use a pikebomb, except that your ballies and pults would also get in on the shooting action. I'm not saying that cavs/phracts in a CD city are invincible, simply that they're protected from maybe 90%+ of players in the game, as they will either not have the knowledge or not have the troop counts to break your defense.

In regard to your CD city, I agree with Bert about beefing up your warriors, if only to add another protective layer. It all depends on what you're willing to feed.

Which brings me to your last question. The following is an hourly food consumption calculator. http://evonypedia.com/Hourly_Food_Consumption I could do it for you, but eh...I'm just WAY too lazy for all that.

As for your #4 and #5 cities, I'd say that if you're going to build traps/abatis, you might as well go all out and put in at least 2k of each. When I put in traps/abatis, I like to put in the number that I think will last long enough for me to get on-line and start actively defending. 100-500 traps/abatis just wouldn't cut it for me.