As far as the 50/50 split question, it's a little more complicated than I can explain at the moment. I will try and explain more at another time, but not now.
Just a thought...
Is the "explanation" , something that your kids will understand 10 years from now ??
Is this something that you want to sit across from them down the road and try to defend your decision making process to them ? Hoping they will understand why they didn't see you more ??
If the answer is "NO" , then do something about it now...
Personally, I don't care to have, nor do I need the explanation...