(in my defence I've only had one coffee and 3 hours sleep) but do you mean as in to ave them live on the floor having essentially a room to themselves, rather than a vivarium?
It's a personal choice really I know a few people who have done it but I personally, don't like the thought or idea of it, though it's in no means impossible to do, presuming that you have the equipment available. On the one hand a full scale open floor space is harder to maintain in terms of knowing exactly what's going on with their health and ensuring everything is kept free from issues and needs much more efficient monitoring than you can have with a bearded dragon in an enclosure. You would need to keep in mind things such as catching a hold of them, how to safely clean it all out, in the event of escapee crickets and how they would adapt from an enclosure to an open space.
In terms of being able to see through the barriers, the potential issue with that is that bearded dragons cannot detect/understand the concept of glass/perspex etc and this can frustrate them, especially if the entire boundary is marked off with glass; it's good to offer them security by non-visual blocks.
Why not consider to simply create your own custom vivarium at the size you would like? 5-6ft and even more are tanks easily created (and cheaply too!) and you can have all the space in the world that you would like for them - it keeps her safe and protected and yet offers her what you want; leg room.
