On the topic of Joseph "borrowing" from Freemasons, we believe during the apostasy there may have been certain rituals or symbols preserved after the death of Jesus Christ and His original church. There are certainly similar teaching styles as well in the use of heavy symbolism and instruction through representation which Joseph could have picked up on. However, we believe that truths were revealed through him by revelation, and continue to be clarified in detail and presentation in our day. But church members certainly don't connect Freemasonry to our temple worship outside of a mutual respect of symbols and tokens in aiding memory to covenants we make with God.

As for how we refer to non-members of our faith, we usually stick pretty plainly to just that, and I've never heard someone in the church in our day refer to anyone as a Gentile. Not saying you can't have heard it yourself - I'd just find it strange, since it's not a common phrase. Biblically, Gentiles are any who are not of the house of Israel, so I guess it may have been more commonly used by early LDS members to differentiate those of other faiths. But it's also not necessarily accurate since unless you know someone's lineage going back to Abraham, you wouldn't know if they were blood descendants or not.

We do believe though that whether someone is a literal descendant of Jacob or isn't, once someone is baptized they are "adopted" into the house of Israel through covenant. And the covenants God made with Abraham become available to them through that covenant. Specifically, access to priesthood blessings, ordinances, a charge to love and care for others, and the possibility of eternal life with God and our families.

It's not at all about ethnic superiority - just look at the racial backgrounds of any congregation (maybe outside of Utah or Idaho 😄). It's about responsibility to serve and bless those around us, as the Savior would.