About heating - it depends on the case, the situation and the weather.
HTc One m9 did heat up very fast, needed to shadow down the display to lowest brightness and 4sec intervall to do steady sequences, but battery went out fast after 1-2 hours
The Honor 7 64GB is quite fine with 1 sec intervall steady for 2-3h in usual case, I use a bike mount and case.
The One+ 3T gets warm, but not too much, does 1sec intervall steady for 2-4h, depends on situation.
In all these three, the Honor 7 is the best so far.
But if you choose your mobile sane,you can get lots of pictures. I can do 3500 pictures/hour, with a external power source I fill the 64GB honor 7 in a few hours.1h with 1sec intervall does produce 15GB data, which needs to be uploaded, too.
Amiga4000 (currently uploading 8k pics from weekend)