Welcome to the forum! I've been getting support here for about three years! It is so helpful to get feedback form others- some more experienced and some just starting out. We are all so different and there are so many ways to approach the lifestyle!
Sometimes there is a motivation based on an ideal or image of how things might be and that image may be very specific like yours.
I would just suggest that although you may be focused on a specific configuration, just remember that life does not always work out exactly like we expect (especially when other people and emotions are involved).
There may come a point when you are in a happy polyamorous life that looks nothing like what you currently imagine!
The key to life is in being fully engaged and peacefully detached simultaneously and authentically in each moment.