I agree, it will take you both some time to get used to the situation. Think about how big a deal it is for you to be doing something totally different with your days now- he is the same. Buuuuuuuuuuuuuuut.... I think you will both get to love it.
For the moment, don't worry about the changes in his behaviour, these will improve again as he becomes more secure in the new state of affairs.
Do try to plan something for each day, but one of the good things is that you can have lazy days if needed, which I bet you could never do before.
I think a mix of activities and time at home is the best. I second things like bouncing babes, libraries, etc. and then cake baking, stories, Cbeebies, puzzles at home.
Try to arrange times to see your own friends with children- you get to have coffee and gossip and he has something new to do.
He should be eleigible for some nursry time and this will also give him some more structure. It will also give you some time for yourself if you are missing the routine and interaction of the workplace.
Wishing you both a fab, fun time.