Does the Buddha have any practices for groups and societies that would lead society to less suffering?
I do have an answer for this part, from Tibetan and Ch'an Buddhism, found in a Terma teaching passed on by the tertön Jamyang Khyentse Chökyi Lodrö. This teaching is about what happens-—and the suffering it causes-—during the Dharma-ending time (now).
Depending and enjoying certain society, one has of course duties in ones relations of which are of many kind for a householder. One not coming after his duties increases debt and endangers to be cut off while still full of desires.
In regard of getting understood the means, ways and kind of approaches, judgement from a wise perspective, ...
The best is the sutta on World Turning Monarch (DN 26).
In addition other two important sutta are Sigalovada Sutta (DN 31) and Parabhava Sutta (Snp 1.6).
There are many other suttas on the values of a great country.
A father-son (child) relation, good householder, is something which is based on debt in regard of the bound of the child toward to ones father and hard to ever pay off, but there is a way, as the Sublime Buddha taught: Parents
This kind of relation requires to fulfill ones duties, found in Sigalovada Sutta
Those duties could be abounded if one goes after ...
Your question is written with admirable/praiseworthy composure. The impression is you have practised the Dhamma very well; particularly from an originally challenging place.
I have previously answered a question at this link about the attitude towards authority figures found in the early scriptures.
Related to this, the scripture Iti 74 refers to the kind of ...
Everybody, yet not reached the stream, is in this way, being an ordinary worldling, not free from sakkāyadiṭṭhi, "On group-holding/identification with it view", bond to be a racist. What ever kind of "ism" developes out of this.
One who would, how ever, try to divide people / beings, into classes, would, if having listened to the Buddhas ...
What I understand from Mahayana Biddhism, "Equality" is the key word directly related to racism matters.
Below are some articles I found online related to the question.
Householders, if wife and husband want to see each other in both this life and the next, they should be equals in faith, ethical conduct, generosity, and wisdom.