You really are suffering with your Gallery, and now your charging problems.

Just after installing the latest ROM, I took a screenshot of the battery just as my phone 'rested'. It behaved exactly as I expected, as you can see.
With the charging, this is also strange behaviour that I have not experienced. I use mainly two rates to charge: the fast wireless, if I need a quick boost; or my 'trickle' Fastboot connection. I can also easily use the phone at the same time as the Fastboot charging. My phone seems to respond as expected.
If I were in your position, as a last resort, I would do as complete a backup as possible with Titanium (and anything else) and do a Factory restore through TWRP. I would then be able to progressively restore apps and data, monitoring as necessary.