I love what u have so far! Great neutral colors. However, I do agree with you the room seems a bit bland as is. U have so many great neutrals. I would suggest getting dark grey drapes to flank either side of the window and accent with golden or teal colors for a bit of pop. The photo above has the warm colored floor and charcoal cabinets, the brass hardware and teal bar stools add a bit of character without losing its sophistication. U could accent with mustard and teal pillows. Do the dark curtain and possibly have a 2nd later under the charcoal drape in one of the accent colors.

I would move the sofa off that wall and make the long end of the sectional be parallel with the kitchen peninsula, so the sofa faces the sliders on the long side. I would get a rectangular dining table to go in between the living room area and the dining kitchen area. The wall with the high windows could use a bookcase, or a console table, a lamp and some colorful art. Some large plants would be good too. You have great light and need some more contrast in your color scheme. See about a stronger color rug and throw pillows if you can. It's a lovely room.

No I don't think you need to get a shorter table unless the one you have is wider than usual (most tables are 3-3.5' wide). I don't think the length is the issue in that room, it's the width. You can just get a bench instead of chairs on that side. Your table is probably 6' long or so, right? Then it will still fit in the dining room. You may want to play around with just putting chairs on 2 sides instead of 3 and pushing it more towards the corner to avoid encroaching on the living room space. 6'+3' = 9' so you'd have 1' to spare. If you want to share some space with the living room you could put seating on both sides.

Here are the pics