As everyone else has said, there is nothing wrong with whatever you decide. But i don't think you should make concrete plans until you have bubs at home.
I assumed DS would sleep in his own room but i found it reassuring in the first weeks to have him close by so i could keep checking on him. Then we both found that we actually slept better with DS in our room as we were getting up often during the night for feeds/comforting etc until DS got the Day/Night thing sorted. DH is a shift worker so his sleep is important too. Sometimes if he really needs to sleep, he just wears earplugs!
DS has been in his own room since about 16 weeks and I hate getting up in the night with it being cold etc - sometimes I wish he was back with us in our room!