I wish I could've had more time with my kids. I wish my then-wife had agreed to 50/50 shared parenting. I wish my ex-wife would be a more collaborative parent. But even as I wish about these things, even as I can feel regret about the lost time, I am HAPPIER NOW THAN I HAVE EVER BEEN IN MY LIFE.
The non-custodial parent is treated a bit like a second-class citizen in the legal system. If you want to go for 50/50 divorce parenting, I think you'll need an attorney. I also think it's worth it, if you want to spend as much time as possible with your children.