Sir basically Eco Mode does not allow the rapid acceleration if a person press the pedal with heavy foot continuously (this is why sometime you feel a very small lag in acceleration) to keep the fuel in economical zone unless your floored your car by pressing pedal abruptly to over take a car. If you turn off eco mode then you can get rapid response of acceleration if you drive with heavy foot.
In civic,in addition to this feature that i explained before, there is another feature of eco mode in which eco mode does not allow rpm to go on higher end and instantaneously changes gears so that rpm remains between 1.5k to 2.5k to keep the fuel in economical zone but if you switch off this eco mode in civic then gear may change at or above 3k rpm like 3.5 to 4.5 or even 5k rpm but gear will not change on 2k rpm. i dont know this feature is also present in corolla too or not because there are only 4 gears
You have to experiment all this to second me .
Sir this meter lightening adjustment is also present in 10th gen corolla i think but we people do not read manuals that's why we have less knowledge of these kind of things. Some people do not like bright light in nights that is why this feature is present. i got to know this just two month before when my car lights got very dim and i thought there might be a problem of battery.