Hey Ossiana, is that your new apartment? Looks good!
Great points about polyamory, I've thought about these a lot. These types of relationships just seem like such hard work to do properly and fairly, I'm certain that the vast majority of people trying these fail for the reasons you point out.
I'm definitely on the monogomous side, I think I could get involved with a threesome where all parties are best friends and committed to each other and really love each other. The other idea of a partner having multiple girlfriends/boyfriends makes me feel a little quesy, thinking of all the different germs and fluids of random people flowing through the relationship! I don't mind germs/fluids of someone you love, but not of random strangers or distant girlfriends/boyfriends that are barely known.
Tbh I'm really enjoying being single and celibate, my life is very peaceful and calm right now :)