[Question] Stock android phone with good battery life

[PaulDaPigeon]

I'm looking to buy a new china phone, last time I bought one solely based on my own opinion. Ended up buying an elephone p10, which was a huge letdown, so now that I need to change phones again I thought I'd ask you guys for some help.

Things I'm looking for:
Stock android ROM, preferably lollipop
Good battery life
A decent backside camera, preferably with flash
Expandable storage or 32 GB internal

Things I would consider a plus:
A rugged phone, I've been looking for one, but all seem to fail at having a good camera.

I usually use my phone for social networks, emails, browsing and watching videos while travelling (ie.: Watching a 2 hour movie on my usual train ride. The P10 could only manage this with minimal backlight or a powerbank, and only when it was new). Occasionally I play hearthstone and some games I picked up in humble bundles, but nothing with intense graphics.

I don't really have a budget yet, but I'm looking to buy something around 200$. I might consider spending more, if it's a rugged phone, that has everything I need.