It seems that once you have about 30k+ rested troops inside a city it seems that even attacking with around 200k+ troops with initial CVs of 200 will never yield any results.
This is contrary to what happened in real life when the Germans were able to capture cities like Voronezh, Stalingrad, and Rostov in 41 through assaulting the city itself. I would try to give examples from the Soviet side but from 43 onwards they mostly captured cities by outflanking them and forcing the defender to withdraw to avoid encirclement. The way the system is right now makes capturing Stalingrad practically impossible as encircling it over the Volga has 0 chance of happening and makes taking Voronezh and Rostov a significantly larger headache than it should be when it's usually captured by axis players in a 42 offensive.
The main issue is the fact that attacks on cities are all or nothing - a limitation of the game engine as units can't remain in the hex after the combat is over. This is contrary to what happened in real life where if the attackers weren't able to drive the defenders out in one go they usually just began entrenching in the buildings that they did capture and urban close quarters combat would commence.
Here are some changes I'm suggesting that are hopefully within the limitations of the engine to try and make urban combat not so black and white. These are just general ideas.
The simplest solution - lower/remove the unisolated 4x urban CV buff for the defender so that cities actually can be taken by attackers without having to always isolate the city first. If this is done then the isolated CV penalty for defenders should also be lowered/removed as well. As even cities with 10k+ stored freight become paper defenders unless 500+ tons of supply is dropped by air which makes no sense.
More complicated solution - Lower combat delay for deliberate attacks on cities/urban from 9 to 5 just like hasty attacks. But also make it so that as long as there are enemy units next to the urban hex, that for every attack that goes past certain odds a small CV debuff (this can be stacked) is applied on the defenders to reflect the fact that the attackers have made progress in the city and more subsequent attacks may soon expulse the defenders from the city. This should give time to the defenders to pour more units into the city to delay it's and incentivize them to launch counter-attacks on the enemy's flanks to drive them away from the city to remove the debuffs.
I hope that the change I'm suggesting above reflects the fact that attacking cities without starving or surrounding it's defenders was a slow and costly endeavor, but possible. There are honestly problems with this such as the fact that it doesn't account for the city defenders itself launching counter-attacks but I'm out of ideas on what can actually be done to improve urban combat to a more satisfactory level aside from the simple changes.
The changes above certainly benefit the axis more than the Soviets, but it honestly doesn't matter too much in a balance perspective as from 43+ onwards the Soviets can always just encircle or outflank cities, they don't ever need to dive into slow grinding urban warfare that the Axis did. Though if they want to, the changes above will let them do so.
Thanks for reading all of this, definitely do not want to seem like I'm rambling and am bringing this up to try and make the game as best as it can be
