I put DD in MCN's at about 2 weeks (after the yukky black poo phase) and she has been in them ever since. I work 4 days a week and DP works full time. The washing has minimal impact on our lives. It takes approx 5 extra minutes per day to use MCN's over disposables plus you don't have to keep taking out the rubbish

Your plan is completely do-able although I would probably do it the other way round first ie. have disposables for sleeping and MCN's during wake times. They look so cute in them that you want to see them awake in them.