Upgrading to 0.77 - baby steps

I’m excited by the new authorisation system that is now in place in HA and for what it can bring in the future.

Given that this seems to be a very big core change to HA and having seen so many threads here about hiccups, problems and things not working as users had expected, am I right to be cautious with my upgrade?

I have not used any of the pre 0.77 implementations of the new system and my config is currently:

http:
  api_password: !secret http_password

and at the moment I have no other network level configurations (and I don’t think it is relevant here but I have no access to HA from outside my network, i.e no forwarded ports).

Before I proceed is my understanding below correct?

  1. Upgrading to 0.77 will not initially change any system behaviour as I have an api_password defined, except that…

  2. Upgrading will present me with a new login screen at which point I can choose to continue as-is or create a user for the new system

  3. If I create a new user (as I plan to) that will become an ‘Admin’ user with full control over everything via the frontend.

  4. (Currently?) this will be the only possible ‘Admin’ user.

  5. This user will be able to add one or more further ‘User’ level users.

  6. Less importantly, my browser should offer to save user / password combinations as for any webpage.

  7. Finally but possibly most importantly, will my future hassio snapshots work in exactly the same way as currently. i.e. will they backup everything including users and passwords?

Thanks, and sorry for asking but it has become a little confused out there which is understandable given the size of this change.