Good on you and yes, you do have to be slightly insane to work from home with little ones, or at least it helps to be so. I have a 21 month old, plus Miss 5 and Master 7, and am due with baby4 this Friday. I work for myself, from home, and would never have started had I been completely sane.
I think the advantage of being an entrepreneur (as opposed to an employee) is that you can dictate your own hours around the needs of the home, you don't have the hassle of office hours, clients can be more flexible than employers, and you get out of it what you put in.
Domestic help is always a bonus, but is not a reality for many women in this country. For me personally, what has helped the most is the realisation that I do not have to have an immaculate house, that it's okay for dishes to soak in the sink for a day, and that every article of clothing in my children's wardrobe does not have to be ironed to within an inch of it's life. I can achieve balance as long as everything does not have to be perfect.
Oh, and the other most valuable piece of advice I can give you is make sure you have a good accountant. Best of luck with your venture, and with enjoying your beautiful babies.