The "nain rukti" would be a technical issue with the braking system somewhere, installing wider tyres is no solution for braking problems ever, we can talk about it one to one kabhi. Problems can be anywhere from low quality rubber (brand won't do any good if they are re stamped old tires, the most common case in the tyre markets of pindi /isl), have u checked the current thickness of your rotors ? Mine were worn out even when the car was driven inside a cantt for the last 5 years which means no aggressive braking, so m guessing they wear out pretty quickly for local assembled hondas that too for an auto.
About the mileage on murree trip, injectors are mostly idle during descent on hilly areas so the combined average comes down to what u get on a highway for a complete trip.
And you don't have a 1970 datsun running mono grade SAE 50 oil, so move ahead of the 10 minute gari geram kerni hoti theory