You sound like you are in a good place, apart from all the dealings with XW. I get the impression that you are feeling good about your choices and you seem more at peace. I hope this confirms that you made the right choice to not move to Toronto! I can only imagine how you would have been living completely on her terms there.
I'm going to encourage you to have even firmer boundaries with XW. There is no reason to let her call 12 times late at night before you silence your phone. She's obviously not calling to talk to the children and there was no emergency, I assume. It almost makes me wonder if she was drunk...
But it is good documentation for how she communicates. It's enough, though, the pattern is going to be clear in court. Now you can show the court how well you handle it to minimize drama.
I think calling for the children at 6:55 when the agreement is between 6 and 6:30 is fine. I would answer even if it's not a special occassion. You don't want to be seen as too strict - it is after all about the children. You don't want to restrict access to the children unless it is extremely unreasonable (demanding you wake them up to speak, calling at 6am or during church on a Sunday, etc.). This is about *their* right to contact with their mother, not *her* rights. Keep that in mind (that's what the judge does) and you can't step wrong.
Her contact with you can be routed through L to minimize stress on you, and it sounds like you're doing a good job of managing that.
Have you visited the SPARC website? deltabravo.net is a fathers' rights group that has amazing resources for fathers.
M 16 yrs, WH62, P54 3 adult blended kids EA 11/13, BD1 6/14 PA fall 14, BD2 2/15 Piecing 2015, BD3 12/15 Separated 4/16 WH moved OW in 5/16 Divorced 6/15/17