Recently did a 700+ Km trip with 4 adults + 2 kids + luggage. This included about 100 kms of ghat section. AC was on all the time. Overall mileage was 14.XX Kmpl. Lower than 17-19 kmpl what most have mentioned.
Problems encountered:  The car felt under-powered even on slightest of inclines in ghats. Overtaking sometimes required 2nd gear. This was not experienced by me in my Wagon R on the same route in similar conditions.
 There is slight vibration in clutch when gear change is attempted at about 3-3.5k RPM. Is this normal?
Experts please comment on what can be done for the above problems. Has anyone else faced similar issues.
My car is Xcent SX Petrol Jan 2018 facelifted model.