Counter point: doing something of your own is going to involve lots of time, so you may get to spend less of it with your child. I think that's more important than the stability factor, although that plays a roll too.
I work from home so I see her when she gets up in the morning, I take her to school when it is in session (she goes half-days during the year), I see her during the day for lunch and snack times (my office is by the kitchen). Then right at 5 I stop working and we all have dinner, then we hang out and play. After she goes back to bed at 7/7:30 I often head back to work and work until 10 or 11.
I couldn't imagine having to leave for work before she wakes up and if I hit traffic on the way home not getting home until 6... I would see her a grand total of 90 minutes a day.
Working for myself also lets us do much more, we take more vacations (since I can work a couple days and keep up) and last year we spent 5 weeks in San Francisco.
If you are raising a family and a startup, then this is a must read: http://steveblank.com/2009/06/18/epitaph-for-an-entrepreneur... - it totally changed how I work and has a made a huge difference for my family.
Do you collaborate remotely, or are you working on your own? It sounds like the home office is really what makes it work out well.
My daughter is about that age, and honestly the home office thing hasn'ed worked so well with her, because she wants to come play with me.
That is an issue that she wants to come and play with me during the day, but usually I let her hang out for a little bit then talk her into going up to her playroom.
At night we all spend time together for dinner, hanging out with our daughter, and then usually 1-2 nights a week I don't work (depending on how busy I am it might be more) and we watch a movie and hang out. (or get a sitter to go out)