I don't like that the pantry and laundry room are occupying prime corner spots -- lots of natural light you could be getting in your kitchen and dining room instead.

I really dislike houses that have the second floor bedrooms in the attic with a tiny window at the gable ends. Our first house was a cape style and although pretty large at 3700 sq.ft, we agreed that we would never want another house with bedrooms in the attic. We prefer a true 2-story house and save the attic for storage and/or hvac equipment.

My family of 3 (eventually 4) is building on the family farm. We're looking for something more traditional, not super open.

This house plan looks like it belongs on a farm -- it would be out of place in a suburb. Since the back will be to the south, the light will be great in your main room, where you'll spend most of your time.

I don't like that the pantry and laundry room are occupying prime corner spots -- lots of natural light you could be getting in your kitchen and dining room instead.

I see your point, but if you flip-flop the house, but these rooms could also block the hot western sun, which can make rooms uncomfortable in the afternoon. It'd be nice if you could enlarge the kitchen window ... and maybe have a pass-through between the kitchen and the living room. It'd allow you to keep an eye on kids in the living room and it'd be a good place to serve snacks during parties.

I also like how the powder room is both centrally located and not within the kitchen's or dining's sight line.

This is a nice detail.

Changes I think I'd make, keeping the house mostly intact -- I'd expand the second story so that the bedrooms and bathroom are lined up with the stairs. This will create much-needed storage in the upstairs bathroom. I'd also pop a window in that room, too.

This would all have to work with a sloped ceiling.

I really dislike houses that have the second floor bedrooms in the attic with a tiny window at the gable ends.

I love story-and-a-half designs, and you could double (or more) the windows in the upstairs bedrooms.

Last thought: You might want to look at the Four Gables House, which has been discussed multiple times on this site. It's a good bit like the house you're considering. It's quite a nice thing, though rather large: https://www.southernliving.com/home/decor/house-plan-of-the-month-four-gables

The time to start working with the architect is now.

In Maine, we design the mud room and then build the house around it. I would want a bathroom with the mud room, to a) have easy access when I am working outside and have a need and b) to hose off mud and manure from humans and dogs. And I would insist on an elevated hose spigot with hot and cold running water outside...which is to say an outdoor shower, without the pesky restrictions of the code enforcement officer.

It wouldn’t hurt to have the washer and dryer in the mud room, either.