My family owns a 2002 civic vti and a swift dlx (both are petrol)
In the city, the swift is preferrable because of its small size and driving around in the city, the comfort is equivalent to the civics.
But on the motorway, on a recent trip in the swift with 4 people, the rear passengers found the swift uncomfortable because it has less rear legroom. the boot is small too which makes carrying a lot of lugguage a problem.
our 2002 civic, despite being a 10 year old car is still very comfortable. its on petrol and has been serviced by honda service center. but because it has covered more than 150k kms, we had to replace suspension parts, brakes, etc which cost quite alot so make sure they're replaced in the civic which u wish to buy
so, it depends on ur usage- for more than 3 people, civic is preferrable but that only if the car has been properly serviced and looked after.. which will be very hard to find in ten year old car. and if u travel to different cities, civic is the preferred car
the swift gives us 13 km/l whereas the civic gives 10-11km/l
spare parts of the swift are cheaper. and as mentioned before, u won't have any problems during the first 50 thousand- 100000 kms. its the best car for city driving and will be hassle free.