I know this is resurrecting an old post, but here is the board and batten we installed in our entrance and on our stairwell. Super easy DIY!

If your breakfast bar is lower than the countertop, it may be difficult to serve onto it from the kitchen side. You have 24" to reach over and then a drop-down. I think you will have problems opening your DW door with it being so tight to the cabinet/drawer handles on the peninsula. The two cabinets at the end of the sink wall, may be awkward to reach into from the corners. Why not make corner cabinets there and carry them onto the sink wall? Your fridge is sort of "out of the kitchen". This may sound odd, but can the doorway to the room on the left of the plan be moved to where your fridge is and put your fridge on the range wall.

Depending on your choice of trim, the windows/doors might end up different heights regardless. I was thinking about this thread a bit earlier while we were at our build and then looking at some other houses in construction. As I mentioned upthread, we have 10/8 and 9/6'8 ceiling door combinations on the 1st and 2nd. Our HOA doesn't allow for 10' on the 2nd floor :( Part of the difference in the feel is exaggerated by the stairs going upstairs being in the great room which has a 22' vaulted ceiling. Going up the stairs immediately there are 2 doors which feel low. To try and combat that, we added crown to the family room there to try and draw eyes away from the door frames. Will report back if that works! Keep in mind too that the width of the doors can also affect the perceived spatial characteristics. A neighbor has the same issue with transition, but on their 2nd floor they have a 5 foot cased opening with 6'8 doorway. I know it's a 9 foot ceiling but walking through it after the 10/8 below felt like one of the seven dwarves reporting for work at the mine. A mix of heights isn't terribly bad. Our basement has 9.5 and a mix of 8 and 6'8 depending if it's finished/unfinished areas. In large open spaces the 6'8 seems fine, the 8 is nice to define bedroom/office area.

Not a Pro. Pictures needed, Sometimes you need to hang same fabric in both rooms, but one room may have for example roman shades and the other drapes.