https://m.reddit.com/r/Android/comments/41g3e2/what_are_the_best_and_worst_releases_of_android/
^ Reading the best and worst Android releases.
My favorite is still KitKat (4.4) and it is also my favorite chocolate bars. I haven't tasted Marshmallow yet but I am aware how nice it is to have the Doze feature although I have double tap gesture to Greenify and Hibernate. I get only 1-2% overnight drain with my LG even if the radio signal is on. Making your sd card combined into internal one is a great feature from MM if you download alot of movies using a torrent app.
My least favorite is Gingerbread (pre-Matias Duarte era) followed by Jelly Bean because JB removed the No Lock app ability and wake screen with volume button. JB might have been huge with Project Butter, but it also was a RAM hog and battery life wasn't quite as good yet until KitKat arrived with Project Svelte. I feel indifferent with Lollipop but I can understand many Android users hating that release because of stability issues, memory leak, and removing features.
I agree with one poster. If KK was the two-year refinement of ICS/JB, hoping Android N is a two-year refinement of LP/MM. Nutella, NERDS, or whatever it will be called will be the 3rd season of the Material Design era, so expect refinements. If Android N is truly that good, then I hope Google releases more Android One devices here in the Philippines. We have sub-$100 Android Ones from our local brands (Cherry Mobile One, MyPhone Uno) that received Marshmallow last year while most of the 2015 Android flagships had to wait for months.
The better Android gets, the better if Google teams up with more OEMs and releases more stock Android devices beyond solely on Nexus devices.