I like it overall, with the open kitchen. Good for entertaining and for watching kids, and the cook isn't cut off. As long as you realize you aren't hiding the kitchen clutter.
I was going to make the same comment about missing coat closets. I assume the utility room has hooks or maybe a rod, but many people also look for even just a small front coat closet. Those spaces also double for storing things like a vacuum cleaner.
I agree that getting to the bathroom through the kitchen from BR 1 isn't ideal but isn't a killer. I was going to suggest moving the bathroom to be private between BR 1 and BR 2 but you probably want it easily accessible to the back door.
In the master bath, I see why you have the door swinging out but I think you are going to hate it. At some point someone will get whacked when the other person opens the door, plus unless you keep the door shut it will probably be in the way as you walk by. Maybe a bi-fold door? Or maybe if you kept that wall with the door angled you could do a pocket door (slides into the wall)?
It is ideal to have natural light coming from two sides in a room if at all possible, otherwise it can seem flat. Many plans would have a window or even a door leading out to the back porch unless there's a privacy issue. You could put the window on the other wall. In BR 1 you'd want either a window in the corner by the dining room wall, or on the other wall, or even both to make a nice cross breeze. Skylights or solar tubes are another way to get more lighting.
The double entry doors look nice but they are probably a lot easier to break into since you can't run a dead bolt into a solid door jamb, unless security isn't at all an issue. It's also harder to put in a storm/screen door if you want that. I would probably just put a single door in the center and panels with glass on each side. I can actually open one of my panels by unlatching it from the floor to make it easier to bring furniture in, but I'm in a very low crime area.
Likewise the back french doors have the same security issue. French doors look cool in the movies but would you ever really use them? You have to secure one into the floor and top of the frame otherwise it can blow open in a strong wind, so when you want to use them you have to unlatch it in 2 places first. Just make sure that you see and understand exactly how they work and then decide if you still want them.
I'd make the side wall against the refrigerator a bit longer so that a full depth one looks more like a counter depth fridge. It looks a lot better than having the fridge stick out, and you don't want a real counter depth fridge because they cost the same but you lose a lot of space. If the counter next to it lined up better with the BR1/dining room wall you could even push it up so that a full sized fridge really fit in like a counter depth one, but it's not that important. Just make sure that gap between the counter and wall is a full 36" to fit a standard width fridge.
Got enough room for a big screen TV with that fireplace on the middle of the wall? If not you could put it in the corner at an angle.
I'd think about a half wall instead of a full wall between the breakfast area and the hall to open up the entry that you'll be using every day. Not sure though. If you leave it full, you probably have room to put a counter and cabinets on that wall if you find you don't have enough kitchen storage, or a buffet.
Not sure about that open garage but I guess it's really a carport with front doors so it at least looks secure from the street. Maybe it's ok to keep the windows from the breakfast nook, even if it's just a view of the cars. It can be nice to have some windows that you can keep open even if it's raining.
Good luck. Building a house can get stressful. This is definitely the time to make changes. Once you start construction, changes get a lot more expensive or impossible.
