Lollipop is pretty annoying. No silent mode and a weird 'priority notifications' mode instead, strange notification icons that don't make sense (* for priority notifications, why?, and an ! on my wifi and cell icons, even though my connection actually works fine).
And the biggest annoyance of all: the swipe to unlock changed from left-right to bottom-up. I keep opening the dialer by accident.
I do like the smart lock tool though, as it replaces a Tasker rule I had for the same.
I think KitKat was the best Android version so far.