I don’t think, with one unit per tile, and the general existence of cavalry in their civ6 implementation, that many players would like to see city tiles that outright can’t defend themselves, a la civ4.
The change from 5 in that you need walls to shoot back is a great change.
Walls allowing city attacks are a way for players to invest production into defense more efficiently than having regular military units. If they didn’t have them we would just build more archers.
That said, I think allowing the “double up” of ranged unit + city strike is a bit abusive (why would you want to garrison a melee unit) and the worst part about city walls is that they scale with whatever the strongest melee and ranged unit you’ve built is. This absolutely ruins the entire wall upgrade line beyond ancient walls because once you have crossbows, ALL your walls shoot at 40
, once you have muskets ALL your cities get the strength upgrade.
I strongly feel that the wall upgrades are a good system that should be extended by (oh boy, here’s Sostratus’ rant again) having each level of wall tied to specific strengths similar to what units of the era have.
As an example, following the loose progression of unit strength, Ancient/Medieval/Ren walls could offer 25/45/55
and 20/40/50
. Since walls have huge HP and massive damage resistance, they’d hold up just fine. You just would be more aware as a player that you can’t pile up some blocks around the city and have full powered defenses in the renaissance.
You could play around with city defenses a little more and even add some extra stuff, like a coastal defense upgrade for cities with the city center on the water that allowed a full damage bombard attack against ships, or late game anti air defenses or bomb shelters for nuclear strikes. (This would imply urban defenses would get periodic upgrades in the tech trees.)
But I don’t think it makes sense to have city defense scale on a dozen factors including the strongest unit you’ve made, which just skews to heavy cav, instead of something where we just treat the walls as a unit class themselves so we have very conscious levers to balance exactly how strong cities are at any stage of the game.
As an aside I also dislike the unit garrison rules and wish there was a better way so it’s not so cheesy to park a ranged unit inside walls, which basically gives you double attack with no downside. Perhaps each type of unit cannot attack and simply offers +5
or
(depending on type) to the city defense.