How to troubleshoot overheating and high battery drain in an Android Device? Device info:


Model  : Micromax Canvas Nitro A310
Android Version : 4.4.2
Kernel Version  : 3.4.67
Device Status : Rooted, Philz touch recovery, Xposed Framework installed


Issue:

My(relative's) device is getting overheated (avg temperature ~ 48 deg Celsius, max reached ~ 65 deg Celsius) and the battery drains (100% to ~9% in less than 7 hours with usage of attending few calls only) very quickly even when its idle. 



About Overheating :

I used CPU Temperature for profiling the apps with respect to temperature. Based on that, I auto-hibernated those apps in Greenify(all experimental features enabled except Telephony Wakeup, working in Boost Mode). 


One main culprit I noticed is the Runkeeper app which requires high-accuracy (more battery consumption) location mode for smooth working. If I put this app in Greenify then it can't possibly be used (will get hibernated) for its intended purpose if the device screen turns off or goes to sleep. 
Other culprit noticed was Google Play Services and Gmail (both updated to latest version) which I don't have any option to hibernate the former in Greenify and I'm not supposed to disable the former because of Runkeeper's demand for Maps and location.




About Battery Drain:

Battery usage from Settings didn't reveal anything useful at all. At the time of writing this question, I've put to test three apps: 


BetterBatteryStats and Battery Stats Plus for profiling battery usage;
DS Battery Saver(free) for keeping the drain low. 


This profiling will take at least 1-2 days and I'm not having high hopes from DS Battery Saver. Another point, my relative keeps GPS Off when not using Runkeeper. Usage of Runkeeper is for around 1-1.5 hour roughly in the morning.



About Device:

The device is only six months old with 2500mAh battery. The surrounding environment temperature isn't much more than 34 deg Celsius to corroborate any additional heating. Furthermore, no new apps were installed before when these issues came into my relative's attention. I take it as some new update in Google Services or other app could be a reason for this. But that is just a wild guess. 



Question:

I need to know how should I proceed to troubleshoot both of these issues effectively? Is there a guide here or elsewhere for such, to do this in a sound manner rather than being haphazard? I aim to pinpoint the culprits here.

Note:

Although I have already made Nandroid and ADB backup, I don't want to reset my device. That is left if all else fails.
BBS is more confusing than GSAM battery companion. It provides more detail, but GSAM + root can tell you a lot. If you could provide screenshots of full charge, to fully dead we can point you in right direction; if this happens in 7 hours with the screen off and no interaction all the better it should be very trivial to find.

From there, you could use Xposed App Opps module to disable apps with excessive spyware.

I don't really help people (relatives, friends) with this stuff unless they're willing to understand 'why' themselves, easier to just recommend iPhone.

There's almost certainly a rogue app running around doing something. A picture would be worth a thousand words