Heat and battery issues on my brand new iPad Air M2 11 inch using non Apple charger.

I recently upgraded from an iPad Air 2 to the 2024 Air M2. I noticed the iPad getting unusually warm and the battery draining fast while browsing, watching videos, and skimming through Twitter/X postings. The heat seems to generate halfway down the backside under the camera.

1) Heat damages batteries and electronics, so I was displeased to note the iPad generated excessive heat during charging. however, I was using a U Green 65 W dual port charger (purchased to charge more than one device simultaneously). Switching back to the included Apple 20 W charger produced less heat AND enabled the 80% battery-saving recharge setting.

Has anyone else had heat issues using a non-Apple charger?

2) the battery on this new M2 iPad lasted about eight hours of what I thought was relatively normal use (half brightness, WiFi only, with many periods of sleep) before reaching my charge start point of 25%. (I believe it’s harder on a Li-Ion battery to drain it near empty.) Granted that the M2 processor is more power intensive, is this a reasonable battery life for a brand new unit?

3) the new M2 iPad lacks face recognition, so it depends almost exclusively on the exposed touch pad/power switch. Face recognition was very useful on the older iPad Air2. Is this a significant single point of failure for the M2?