I would not worry about grinding rapport in battle. Some of those combos are not great, but mainly because you get absurdly more rapport points from meals at taverns than you do from fighting in the same squad.
https://i.ibb.co/Twbb1b6/20240223-211737.jpg
https://youtu.be/qj9p6IFSlnk?si=cZ5L4OPM0TjVjwCD