1) In regards to the advanced calling, it primarily works when you are talking to another Verizon customer. I've noticed the difference when my phone updated and i made a call to someone having the S7 edge. the new feature of video calling is Verizon version of Facetime. It's pretty cool and comes in handy when talking to another Verizon customer.
2) I haven't had that happen to me, but i have noticed that some apps have changed. but you can always set your phone up the way it was prior to the update that ha come out. Trust i know it could be a little irritating but once you get everything situated, it will be ok.
3) i've noticed that as well. But it does it very intermittently. it is most aggravating when you are trying to use the data and realize that you don't have service that you are paying for.. I just hope that is going to be a patch coming out so that this issue is going to be fixed.
If you are anything like me, you enjoy the note 4 and know that they are going to be phasing it out towards the end of next year. I just look forward to see this upcoming note 6/7. well i hope that this helps as well as all the information that was shared.