Its hard to get an idea of the size but it seems like a small space. You don't have stick with the exact same color but try to use the same color family so the rooms will flow , visually expanding your home. A colored ceiling can be chic but again that depends on the size of your space. In a small home I would not do that.

I think I'd stick with one color for all the walls since your like small accessories. How about a very light sage green? Then, the trim and ceiling a creamy white?...test the two colors together to make sure they compliment each other. These colors may work with your floral (nature) inspired decor.

I do so love the definition of an American "small space". From a british point of view, it seems quite large to me. You would be amazed how small an average home is here!

Beautiful flooring. Wondering..... and it may be a bit quirky.... but if you start breaking up the walls with colour I think it will look a bit odd, due to the open plan design. My idea to "separate" the dining area would be to paint the ceiling of that bit.

I see two sets of chairs but am not sure how or what they link to. Don't think we're seeing the kitchen.

Sorry you couldn't see the kitchen from the picture I posted before the set of two chairs are bar stools at the counter.