If there's one thing I've learned over the past year, it's that any employer worth working for will understand and support your need to spend time with your family. No sane founder would ask their employee to put the startup above their family.
A few other tips:
- Take 15 minutes to yourself every morning, get a cup of coffee or tea, and read HN.
- Listen to industry podcasts on your commute. I'm a big fan of ShopTalkShow (front-end dev), This Week In Startups, and Javascript Jabber (between these three I almost always have something to listen to between work and home).
- Twice a week (YMMV) wait for the baby and lady to go to bed, then hack for an hour or two. Don't do this more than a few times a week though - I used to never go to bed with my fiance (always working), and we started growing distant and fighting more.
- Use time at work (especially lunch breaks) to play with new technologies
- Help your wife with the baby wherever you can. She put her career completely aside for your child, so she'll need to see that you're making sacrifices too and giving it 100%. Your relationship with your partner is invaluable.
I'll end this list with one final piece of advice: cherish the time you spend with your family, and hold it sacred above all else.
I'm currently in SF doing some contract work with an early-stage startup, about halfway through a 1-month tour. It's been harder than I could have imagined; and while I FaceTime with my family every day, the extent to which I miss them every day has really helped remind me what's most important.
I hope this helps, and if you ever want to talk some more (or hang out, since we're both in SF for now), send me an email: address is in my profile.