There is no point n trying to 'win' defending your city. Same thing in PvP. lose. It is way easier, far more peace of mind. and you can get on with yor Foe life. knowing you will never be able to defend your city, nor win defending in PvP. (One hint, never PM the attacker with any kind of message whatsoever. none.)
I learned a long time ago there is no point what so ever in trying to protect your city by having a strong defending army! There is no point!
It is a waste of resources.
Have some (small) city defense. Just so you're not totally wide open, but expect to lose most of the time.
I am in Venus Era or SAJM in my Worlds and have no practical ciy defense. (I use one Bronze era Spearfighter) ditto in PvP.
Newer player get way too bent out of shape worrying about attacks on their City. relax.no one cares! Get ver it
THere are only two good things to do. Attack back (even if you lose, you might gain a little respect), and collect your city on time.