Z5 Premium owner finds missing features, issues (& bugs)...COMMENT PLEASE!

Hi there. I've recently bought a brand-new UK SIM-free Z5 Premium over on eBay. BRIEF DISCLAIMER: This is my first Z5P but had various Xperia phones in the past and have been documenting issues on phones which i find to be consistent with my personal use with the dozens of reviews I've read. Such missing features (& bugs) were:
1. Camera - No option to change scene (SCN) when on Manual mode, still takes (almost) 3 seconds to bootup and over a second to process/save the photo.
2. No realtime / always On battery saver mode (unlike what Samsung and other OEMs have implemented)
3. Still stuck at 6.0 (not 6.0.1) and a February 2016 security update
4. If battery goes below 20% and battery saver turned Off fingerprint scanner is disabled
5. No dark mode - I cannot find a suitable Theme that offers a dark wallpaper or Settings background that can help me save battery life.
6. No night mode - An added feature to enable to read text comfortably at night
7. No built-in Memory Cleaner (unlike what Samsung has implemented)
8. No Xperia-centric App store (again like what Samsung has implemented)

I can understand the phone is over a year old now but surely the software should be on 6.0.1 and a December ('16) security update. Surely.
I found it "painful" when ringing the UK Sony Mobile customer services as it sounded like Sony is living on a different planet, refusing to acknowledge such issues (blaming me as "it was my own opinion" have never heard such problems in the past) and seemingly suggesting that in order to trigger an action to investigate they need such & such percentage of their users before they can act which i find disturbing and unacceptable. These are the things I think are quite basic and should have been sorted long time ago.
I bought an Xperia because of the build quality and hardware. Now, I'm having second thoughts.

Any advice, comments, suggestions & thoughts please?