That sounds like a nice gap FOD. I know it works for some but DP and his brother are 4 years apart and they didn't get on at all until they were adults. My young cousins are the same, the eldest got used to being spoiled as an only child and when his sister came along he was really jealous. There's 2y 2m 2d between my sister and I and we've always been really close although I apparently threw an almighty tantrum when they brought her home
I would be looking to go back in Jan and start trying again in Mayish. I am not risking another Christmas due date! Doing the Christmas food shop 5 days after giving birth was hell on earth! 
If I win I'll cut you in if you do the same Honey! I'd have 4 DC then! What's your PhD in? I have one in Biochemistry, I have a good job but it's a huge commute (40 miles ew down the hellish M6), which will mean that I will be out of the house long hours. When I go back I'm going to ask for 4 days, 1 from home.