Firmware update usually don't bring about a significant change in battery life. As much as apps and system core are optimised each time for battery optimisation, users will still need to help themselves in maintaining the phone with the removal of unnecessary apps and to impose stringent rules on apps, such as disabling background data/notification etc...
Tab s3 can last for very Long in my own experience but you need to remove some of the unnecessary apps in order to achieve that far..
The latest update fixed the sensitivity on my fingerprint scanner. It is way better than before the update. I used to always go to the pin code as my fingerpint is not properly scanned.
Now, it is good. Happy with it.. I am also happy with the official keyboard casing that I got from Amazon for USD $64 which i ordered 2 months ago.