Essentials Smartphone

I am looking to upgrade my semi-smartphone to a top end one within the next couple of months. Often, we buy phones for qualities which are not core to a phone's essential capabilities like camera, screen, apps and I too started off on that trajectory comparing cameras, platforms, screens (ppis) et all. I had a conference call today and had to dial in a third person to the call - trust me, my phone literally acted like this was a herculian task. And after a couple of hours, the battery almost died. So I would like to know which smartphone in your expert opinion would satisfy the following:

- 6 to 9 hours battery life with moderate usage

- Solid mapping solution (preferably google maps) but also the option to have offline on-device maps (the caching option sucks on gmaps)

- Excellent call reception and noise cancellation

- Conferencing capabilities - the phone should not hang trying to conference two calls

- Most smartphones get slower with use (and all the junk we keep feeding it) - a robust restore option- seamless, painless

- a good camera - dont want a 41 MP or super stellar low light camera - just a good one will do, which takes sharp accurate pictures during the day and ok pics at night.

- timely updates from the platform (not must, but good to have)

- something that would last me the next 3 years

Which one would you pundits suggest with no bias?