Remove the girls from the conversation first.
Keeping them in it just reinforces your sense of not having an ability to improve the situation.
The first thing I saw is-
Your work schedules inhibits you from having the type of personal time alone with him that you want.
SO HOW DO YOU SCHEDULE THAT ALONE TIME.
Even in mono relationships with children-it is IMPOSSIBLE to have sex "whenever and where ever you want". I have MORE ability to have unhindered sex and alone time with my guys now then I ever did mono-because one or the other can take the kids so I can have one on one time with the other guy.
YOU are unhappy with the amount of alone time
You are unhappy about the quality of alone time
In either case-you need to look at what YOU can do to change the situation between you and him.
As for bedrooms-I don't even know what to say to that because I don't understand why you can't have sex in your own room. That makes no sense to me at all.
"Love As Thou Wilt"