Very well narrated. I also keep an eye rather record on app regarding fuel avaerges and running costs. You mentioned swift, wagon R vxl and alto AGS, luckily I have had experience of all of these.
Swift DLX 2012 bought brand new in 2012, disposed in 2014, 30K driven as secondary car mostly by myself. Fuel average 10 to 11 local and max 13 on long with light foot, (No phone app, yes manual Full tank to full tank observation).
GLI 2014 OLD shape brand new and disposed in May 19, dove 103K mixed by me and diver. Fuel average 11 plus in local and 17 max on long, all log maintained on app My Cars.
WAGON R VXL bought brand new in 2015 disposed in 2017, daily runner 49K driven, max average 23, average in two years 15.7 km/L, fuel n maintenance log on My car's App.
JDM stingray 2014 model bought in 2017, disposed in Jan 2020 drove almost 75 K in two years, fuel average local 15, long 20 plus, log fully maintained on My cars app.
Currently using BR-V 18 model got it new, almost done 47 K gives 9 in local n hardly 12.5 in long.
Currently ALTO AGS bought in Nov 19, done 9200 Km gives 17 plus in Local and surprisingly max 25.5..
Just to add my experience and let you know about the fuel efficiency from different vehicles, surely with different makes and uses, but this AGS alto seems to be best for daily city drive with all useable features in Pakistan, warranty and ease of parts availiblility. For long routes and sedan category corolla that I had was winner.