Welcome to the forum! One of the most compelling aspects of poly-for me- is the fact that it's totally outside of the cultural "norms" most of us were raised with.....and as a result- there aren't many role models, but they can be found!
I am still a newbie (committed poly for 4 years) and the one thing I have learned is that it takes a great deal of emotional maturity (which you seem to have) and other than that it takes letting go of the need to "know how to do it" because it requires for each individual to figure things out for themselves. It demands authenticity.
The boundaries we had set in the beginning (for "protection") are melting away and we are letting a lot of them go. It's very freeing!
Me and my primary partner have allowed the lifestyle to pull us along like a river and we can see that we are growing and allowing ourselves to change organically- and we experience moments of great ecstasy! We are falling in love with one another again after knowing each other for 12 years and we are loving other people too! It's a great adventure!
Let it flow!
The key to life is in being fully engaged and peacefully detached simultaneously and authentically in each moment.