Lollipop has been a big disappointment for me.
1) WiFi keeps dropping and reconnecting.
I think this is a result of a bug in the Smart Network Switch setting in the Advanced Wifi settings (Settings-->Wifi-->options button (vertical dots)). It is supposed to automatically switch back to 4G if wifi drops internet (not drops signal, but drops the actual internet connection). My wifi losing and regaining connection problem has gone away after I unchecked that option.