@lightspeed2slow You moved to fast Into this. Your only 8 months in so I wouldn't say that I would expect him to be heavily involved with my kids yet, but since you've already moved in with him he kind of is and ignoring the kids and sleeping in drinking to late is going to set a odd example ...
@debbiedee I don't think it's a terrible idea
You could also move your bed into the living room and give your 3.5 year old there own room.
Pinterest has a lot of good layout ideas for incorporating a bed in the living room.