I didn't have kittens when my DS was a baby but did have 3 cats. Never had a problem at all apart from being extra vigilant with my female cat who was the sweetest cat ever and would have tried to snuggle in with my DS in his Moses basket. My DS weighed only 4lbs when we brought him home so had to be very careful. She loved to sit as close as she could get when I used to give DS his bottle.
The other two cats just weren't interested and would shoot out the cat flap when he started to cry. I had more problems when my DS was a toddler, not with the cats but with him! He could get a little rough with them so had to teach him to be gentle. He did get a couple of scratches but in my opinion it was part of the learning curve. We still have cats (although the original 3 have long passed away) and DS is now 16 and adores our cats.
I guess it would be harder with a kitten though as it would have to be kept in until neutered which will mean having to clean out litter trays and you will need to play with it to stop it getting bored but as long as you and your DH were committed to ensuring the kitten also had some of your time then I would go for it.
Cats can be neutered at 5/6 months so she could be an outdoor cat by December, but you'll still need an indoor litter tray. I have 3 cats and am due my first baby in March and I plan on keeping them all! I'm not saying it won't be difficult but I don't think I could give them up. I'm going to tag a long on here and see if anyone has suggestions on keeping cats out of Moses baskets ect!