Design Dilemma

These photos are terrible, but I wanted to illustrate one of my most befuddling design dilemmas.  Our main floor consists of this one long room, and I love the openness of it, especially now that our kitchen has become part of the room.  However, that big long wall has me stumped.  How do I differentiate between the living room and the dining room?  Or do I even bother?  Do I fill up that empty space, or leave it? How do I make one room flow into the next without making it just one big rumpus room (which let's face it, it is!).
Behind the sofa I currently have the kids little craft/snack table, and that teak side board is stuffed with craft supplies.  The back area by the door of course gets a lot of traffic, especially during the summer.  I did have a rug under the table but with the two messiest eaters in Canada living under our roof, I moved it down to the basement.
My latest idea is to put six matching white frames there - I was thinking I could perhaps use my own photography, either of the kids or of the more artsy flower-type shots.  I am hoping that they would make kind of a 'focal point' for the dining room to balance the mirror/fireplace combo in the living room.
I put up the paper to get an idea of where I would put them and what size they are - there was no measuring or science to this mess (only the top 3 are the actual size of the frames)!  I think they would go a little lower, and slightly closer together.  But what should I centre them on?  I guess the table, but we move that from time to time... And is six enough or should I do eight?  Or is this a truly dumb idea?  Help?