Good afternoon!
Those plots look good. I'm glad you got all the way through alpha rarefactions plots and bar plots.
Your questions are also good, and many of the answers are in the tutorials. For example, when you ask,
That's a good question that's answered in Moving Pictures tutorial. Bonus, there's also a translation of the Moving Pictures tutorial!
Take a look at how the Moving Pictures tutorial interprets those results, then let me know how they compare to your data.
Then we can help answer any more questions you have.
Colin