I'm trying to put myself in your shoes and imagine that extra 20 minutes each day just on the school run alone. So currently it takes you 5 minutes to get to school and 5 minutes home again (10 mins, 2x per day = 20 mins in the car to do the school run). If you move it will take you 20 minutes to get to school and 20 minutes to get home again (40 mins, 2 x per day = 80 mins in the car to do the school run). That to me is huge, particularly if you have another child in the car that is stuck in the car for an extra hour.
Also, factor in hubby's additional travel time of an extra 30 mins per day, which is 2.5 hours extra per week.
Note: I may have confused myself and be totally wrong in my calculations, so if i am, I apologise.