>My question is, should I make all the dogs stay down off the furniture to keep peace among them meaning they all know their place, etc? Or would it make any difference if I made the top bitch sleep on the floor(in a bed) and let the 4 yr old on the sofa?
It often depends on you and your dogs. In any given situation my dogs are perfectly capable of managing their own order. The fact that I might choose to perform one action with one dog doesn't really figure into their equations.
However my MIL is inclined to to exagerate the attention she pays to one dog - and it draws the others in a way that often results in some pushing and shoving. I'm not sure how she does it but it's very obvious when she is around that there is some inequality. If you were going to allow your 4yr old access to the sofa and continually reinforce that the older one isn't allowed I'd say that you are going to create an unnecessarily awkward relationship for them.
Pack hierarchy, such as it it is, is a floating beast in our household and depends on each situation. Walks, food, beds - all seem to have different leaders and followers depending on how they feel. If anything ever upsets the status quo I just watch and learn for a while and they seem to make adjustments to compensate. I could feed one first or last, it doesn't seem to matter - they have their own rules and rituals and anything I do is outside of that. I don't need to impose a 'pack' order on them and I'm repaid with a pretty easy life.