K.,
I had my two children a year and one week apart. I was so excited to give my son a play mate and hubby was excited at the idea of having them both out of the house by retirement.
I am now excited about getting a body back (despite stretch marks and excess skin) and never being pregnant again.
If you know you want another, I think now is a good time for you. They will be less than three years apart which will make them close as anything more than three years is two different worlds in my opinion. (My sister and I were 3 years apart and we just were never in the same place even though I desperatly tried to fit in with her.)
Your daughter will be roughly 2 1/2 when the baby is born which is the perfect, "mommy's little helper" age. My son tried to change his sisters diaper this evening. He gets her blankets and milk.. ect. He wants to take care of her because that is the age of a 2 1/2 year old.
The further apart I think the worse off because once your daugter starts school, she may even get jelous of the time you will have to spend with the new baby when she gets home from her long day and she may feel left out. Rejection or competition is a dangerous emotion for children.
I hope I've helped you in some way. If you're still really not sure, pray about it. You'll know when the time is right, He'll tell you.
J.