Honestly, can't believe what I have just read, everytime OP tried to make a point she sounded more and more unreasonable.
So you refer to his partner as his 'girlfriend' meanwhile your partner is stepdad despite you all getting together around the same time, you are annoyed about his fathers day meal being ruined for stepdad but refer to her as the girlfriend and describe she takes time to do the children's homework and reading with the kids
It's an issue that Dad is spending time hugging his girls when he will clearly miss them as they are far away and he doesn't see them everyday, I would be more concerned if he wasn't showing interest or affection
You are unhappy he has toys and clothes at his house he has purchased, do you happily hand over all the stuff you have bought? Guarantee you don't, the kids should have belongings with both parents
You complain and say he would rather work on Fridays than pick up, have you considered he needs to work, don't know many people who would rather work than have time off
Overall you have managed to come across as difficult and obstructive and clearly don't sound like you have the children's best interest at heart and are totally unreasonable, most people would consider stopping contact for serious issues such as neglect or the children being in danger and all you have described is a father who is dedicated and cherishes time with his kids. I really can't see what the issue here is other than you OP. I feel really sorry for your ex