Your pictures don't enlarge so it's hard to see what you're talking about, but if you're thinking of removing a wall, I wouldn't paint the rooms different colors whether you added a shelf or not.

It's the floor to ceiling cabinet I might remove. We would replace it with a 1 foot half wall topped with a fluted column along the wall to the ceiling. This would create a divide between the two rooms so I could paint them different colors- not too different. We already have a half wall on the other side so we could add fluted trim to that side. Or we could just keep the cabinet that we have. Not sure what to do. You can see the half wall on the right and the tall cabinet on the left.

Thanks for your help.

This is where one would normally expect to see columns on your pony walls.

What you have gives you the best of both worlds. Leave it alone. Being hold up, winter, after the holiday busy gets to a lot of us--"what if we..." becomes common conversation. LET IT GO!!!

Not sure how it would work for you but I can share how we arranged it in our kitchen/nook/family room. We used a curved soffit in the ceiling and matched the curve in the flooring change by the island. A bookcase with tall lamps help divide the space while still leaving it open.

Love the colors you used. I see that you are using 2 different colors. It looks great.