The garage and laundry are accessed through the bedroom?

Is it to be a vacation home for you?

Laundry and garage can be accessed through bedroom, garage door, or secondary door on the side of the garage. After renovations we will live here full time.

All bathrooms have to be accessed through a bedroom?

Where were you thinking to have the bathroom for the third bedroom? I would consider a stacked washer/dryer upstairs.

I would make the third bathroom a "hall bath" so that dinner guests don't have to walk through a bedroom. Take the upper part of the living room (the side that backs to the dining room) to make a bathroom and a closet. Hallway on the left side of the family room connecting to the bathroom, current second bedroom, and new third bedroom.

Which side faces the lake? I assume that at the top of the floor plan. If so, you would want to keep a living room on that face.

Are you gutting the inside completely? Do you want to change how you get to the laundry? What is the scope of your project?

The design of a house begins with the site, then the owner's needs; same thing with a remodeling. Without that information you are receiving misguided enlightenment.

Your gut should tell you to contact several local competent residential architects to see which one(s) you feel comfortable working with. They will be able to gather the appropriate information needed to meet your needs and fit the site, whatever they may be.

Are you going to be redoing the septic then? Because nothing is worse than not doing that, and ending up with reflux. Which is what happens frequently with old home that try to add on capacity to the house, without capacity to the waste processing.