i think the push rod thing is there to prevent any over heating in these cars, i remember my brother's 2007 mira's AC got blown by idling AC during traffic, i have personally also faced this issue, so if i am stuck at a signal i just put car into N
ECO-IDLE needs to be charged before being enabled to use, thats why you need to travel a few km's for it to trun to green
just look at rpm in case you are not sure if engine is turning off or not as if it is rpm should be dialed back to zero
in my personal experience, realistic mileage within city(Lahore) is around 19 in winters and 17 during summers because of AC