For me the battery is much better, I used to get just under 3 hours of screen-on time and now I usually get close to 4 hours. This is with moderate use. Wifi and bluetooth always on.
Silent mode can be accessed by pressing one of the volume rocker buttons, and then pressing on the bell icon next to the volume bar. It's a bit of a hassle and I would have liked it on the quick toggles or even better the power menu as it was on KitKat.
The torch is nice, but I picked up a bug with mine. If the screen locked (time-out) the torch went off, and I could not switch it back on again. I had to restart the phone entirely.