GF wants to go back to court

My 35f gf has 2 kids 9 and 10, and wants to go back to court with her ex-husband over what i consider to be his mild violations of the parenting plan. State of Illinois. Both kids are doing very well by any objective standard.

Recent examples, exchanges are twice weekly and the Father is about 15 or 20 minutes late on exchanges 10-12 times a year. This is generally just his bad planning or lack of punctuality. A friend of the Fathers called dad's new girlfriend "the step mom" in front of the kids which my gf believes to be in violation of the parenting agreement, and im not so sure of.

I advised my GF that I think these are relatively minor issues and I believe that this is an emotional response because, shocker, the two people who couldn't get along when they were married still cant get along. I dont think its worth it financially to purse this, and im unsure what the remedy would be if she did. I told her it seems unlikely to me that a judge would be willing to do much on this, especially when the children are flourishing as is.

Am I way off base here? If im not too far off, what is some good phrasing to use in my conversations with her that keeps me out of the doghouse and gets the point across?

Thanks Reddit!