City for sure.
Apart from looks, it is reliable as I drove a city that had been on a rent-a-car for 3 years without proper maintenance and it was driven on routes like muridke narowal, gujranwala, lahore and sargodha and it remained strong.
It is quite comfortable.
The spare parts are affordable when compared to lancer and liana has very expensive spares too.
Economy wise, there is no match for idsi engines, period.
City has the best resale amongst these three and this is no hidden fact.
Lancer and liana do have issues on CNG even if many disagree but I have seen many suffering. If you are amongst those who don't you must be lucky yet why to try luck when you are already spending all you have for this purpose. Blown up coils really cost a lot, once a lancer guy was purchasing those and spent 35K on only coils and the mechanic plainly told him that it could happen again and again. Liana also, if it develops issues, it will remain having them, especially on CNG and don't ever think that being a suzuki, its solution will cost any lesser than honda or mitsubishi.