Hrvatski Noahid on the basis of what are you making a connection between kindness and the Noahide commandment of laws and courts?
Noahides are given a reward for honoring parents - is this too, according to you, part of the Noahide commandment of laws and courts?
Rashi informs us the mother of Amon was rewarded for her good speach for not explicitly saying Lot was the father, unlike the mother of Moab, is this too related to "Laws and Courts"?
How do you explain the future celebration of the nations of the festival of Succot according to Zechariah Chapter 14 verse 16
Please don't say "according to you." I am a Croatian Gentile who cites the teachings of Orthodox Rabbis, not my subjective opinion.
Societal morality and the obligation of doing kindness is part of the Noahide commandment of laws and courts (the Divine Code by Rabbi Weiner, Third Edition, p 692). This includes honoring parents (the same, p 694).
The prohibitions of embarrassing another person, evil gossip and tale-bearing are part of the Noahide prohibition of murder and injury (the Divine Code by Rabbi Weiner, Second Edition, p 453).
Your question about Zechariah is poor scholarship. We do not use from the prophets against a sefer halaha. But there is a good Chabad article called "How a Gentile Celebrates Sukkot" which answers your question:
"Zecharya’s reference to the sukkah is an allegory.
He does not mean that in Messianic times the gentile will be obligated to eat in the sukkah together with the Jew, and be punished if he does not fulfill the mitzvah. He means that the gentile world will be expected to practice the lesson conveyed by the mitzvot of the festival of Sukkot. They must forsake their striving for selfish gain and replace it with a sense of responsibility and sharing of privileges with all of humanity. Hence, Zecharya’s words, “Lo ya’alu lachog et chag haSukkot” — “They have refused to go up to celebrate the festival of Sukkot” — can be explained to mean that they have refused to elevate themselves spiritually and realize the message that Sukkot teaches humanity."
https://www.chabad.org/library/article_cdo/aid/2829272/jewish/How-a-Gentile-Celebrates-Sukkot.htm