There seems to be a lot of bathroom space and very little living/dining space.

Eleven (11) bathroom sinks?

Is this some multi-family vacation house?

Yes, it is. We have three children and each one with their significant other so they will have their own bedroom with its own bathroom. Hmm... I didn’t realize that there is so much bathroom space compare to the living space. I will check carefully. Thanks

And will all of those children and significant others live with you in this house? They don’t seem to have much closet space, nor storage at the bathroom sinks. Perhaps they could get by just fine with one sink per bathroom, and more drawers and counter space in the vanities.

Are there, or will there be, younger children?

Do you need an “away” space, or are you okay with being all together all the time?

Do you need a den or study for paying bills, storing records, private phone calls, etc?

Is there enough dining space for everyone?

Is a 2-car garage sufficient for everyone?

What are the little courtyards off each bedroom?

Where are you building? What is the site, and climate, like?

I suggest you lay out furniture in each room to see if the spaces accommodate your needs. If all of your children and significant others show up at the same time, will you have enough space for everyone to dine together inside? Does your family watch TV together? Will you have enough seating for everyone?

I agree with bpath and chispa’s comments. Counter ”real estate” in a bathroom is often more valuable than a second sink. Which will your family appreciate more? A second sink or room on the vanity top to spread out hot rollers, make up, hair dryer, make up mirror (and a place to put it all away)?

If if this is a beach house or ski house etc, I suggest you have an area to store all the messy stuff and clean off messy feet etc before you enter the main living areas. I can’t tell from the plan if you have that.

You may also want to consider how much space you give to the MBR suite vs the space you give to the guest rooms. How much time will you be at the house without your kids? I expected my kids would want to come to my beach house a lot. But in reality, my grown kids have only a few weeks of vacation time which they split up between us and in-laws and their own travel. Once grandchildren come along and have their activities, getting everyone together at the same time gets even more complicated.

One more thing to consider — the U shaped outdoor space on the garage side of the house may get little sun, depending on how the house is situated. This may limit your landscaping options. If the area is in shade, water (or snow) may not evaporate quickly, which could be troublesome. You may want to talk to a landscape architect to make sure you have proper drainage and a landscaper to see what you can grow if that area is shaded most of the day.

I look forward to seeing photos of the house as you build it.

I've seen plans like this a lot in Hawaii - I'm guessing this is a house in a tropical location of some sort, so there's more limited indoor space because there's an abundance of outdoor living space? And you're building bedroom capacity for all of your adult children to visit simultaneously?

One thing to think about is how the house works if/when you have grandchildren. Right now none of the bedrooms are easily accessible to the others. That's a plus when there are couples in each, but it can be an inconvenience when one bedroom holds the parents and another the kids. In that situation, our extended family has found that what works best is if there is a small room (even a large walk-in closet, if it has HVAC and ventilation) off of a bedroom that can be used for a crib or child's bed.