Good Sims don't generally consider performing mean interactions on other Sims.
Good Sims will not have negative reactions to social interactions as often as other Sims.
Good Sims will boo other Sims who work as an Emperor of Evil, the top level of the criminal career's Evil branch.
Good Sims have an easier time befriending unicorns, as the relationship between the good Sim and the unicorn will increase faster.
Good Sims are sympathetic, and will appear genuinely concerned if another Sim is experiencing misfortune, rather than laugh at them. They also will be sorry for a Sim who has caught their partner cheating in front of them.
Good Sims will not be able to fight a burglar, even if they have brave or Can Apprehend Burglar traits. Also, because good Sims cannot initiate the "Fight!" interaction, the increased chance of winning fights from the Can Apprehend Burglar hidden trait has no effect. Good Sims still retain the increased chance of winning fights from having the mean spirited and/or brave traits however. In bars, clubs, and lounges (except future lounges), they are still able to initiate brawl, like other Sims.
Strangely, good Sims can have the mean spirited trait, which is considered equally mean to the evil trait
"Don't consider performing mean interactions" means actually having most mean interactions locked from the Good Sims, even if they also have the mean spirited trait. As a general rule, only mean interactions related to anger such as "Argue", "Accuse of..." or "Yell At" are available to good Sims. Mean interactions that pose major changes to relationships like "Break Up" or "Ask to Just Be Friends" are still available to Good Sims as well.
Good Sims get along very well with most Sims, except for evil and mean spirited Sims. They will also autonomously complain about a Sim with the inappropriate trait, and will never accept their "Make Fun Of..." interaction.
Good Sims have more success at cheering up Sims who are angry or upset. The same goes for friendly Sims.
If the Good Sim has been made an enemy of by another Sim, the good Sim will gain a wish to propose a truce with the newly made enemy.
Good Sims will often gain wishes to congratulate other Sims in the neighborhood who have just married; even if they are enemies.
Good Sims tend to respect other Sims in the law enforcement career, but will disapprove of any Sims in the criminal career.
Good Sims are always shocked at Sims dying, even if it was their nemesis - they won't laugh at their fallen non-household enemies like other Sims.
If Sims are wearing the wrong clothes at the wrong time, Good Sims will boo in disapproval, but never point and laugh at them like other Sims.
Good Sims tend to talk sympathetically about Sims experiencing unfortunate events around the neighborhood when the "Gossip" interaction is used on them.
Good Sims will receive this moodlet by donating to charities. This moodlet will last for a full 24 hours, and add either a +10, +15 or +30 buff to the Sim's mood depending on the amount of money donated.
Other Sims who receive the "Brighten Day" interaction from good Sims will receive this moodlet. Lasts for 3 hours and adds a +10 buff to the recipient's mood.
Everyday I'm Rustlin
Good Sims who don't return a borrowed horse later than 11 PM will receive a negative moodlet with a -30 mood penalty instead of a neutral warning moodlet.