Re: Training 20+ Years (or longer) question
I had less guilt that I might have because my son and I did aikido together. We started when he was 5. But then I had another child and I had more to balance in the equation. A dojo mate had a good compromise--train once a week one week, then twice a week the next. When you're at the dojo, really be present. When you're home, really be present there. It's hard to be torn, I know.
Once my daughter got older, I taught the children's class, so I got to do aikido with both my children. Also, I was really lucky to have an extremely supportive spouse, but of course I returned the favor so he had time to do the things he loved, too. We both wanted time with the family, with our kids, with each other, and with our own activities. Managing all that takes negotiation and unselfishness, but with good communication you can manage all of the above.
I see a couple in our dojo. They have young kids and they both want to train. They trade off nights and once in a while they get a sitter so they can train together. They make a night of it and go for a nice dinner afterward. Good luck! Your baby is going to grow up so fast. My 5 year old aikidoka turns 28 in less than 2 months.