What do you mean by family area? You have a living room . B is certainly better living space. You have nowhere near enough information, full dimensions, of every space to even comment.

Option C: Sell this and move to a larger home.

It is hard to compare when you have no existing plan to relate to, and visualize what would happen with say an existing vaulted ceiling over the Kitchen/Family. But in terms of any addition, I would guess that both your schemes offer complications that an Option C should be considered (C, D, E, F . . . as in more schemes, not moving).

If the garage is to be divided, I see some unrealistic expectations.

I would need a ton more info. How big of a family how much entertaining , I assume the FR is where the V will be so where is that planned . I like the slanted wall design wise but this needs to fit your needs and style and that slanted space will create some interest but also some challenges to furnish.Please post more info here in a comment DO NOT start another post. O aslo need to see the house as it is since you say this is an expansion and why the garage divided .

What is meant by ”straight staircase wall”? We need more information to help.

@res2architect Set back on the right is new wall so we need to follow new setback which is 6ft. Right wall is old and it is existing setback of 5ft. Existing floor plan

The OP is only asking us to choose between A and B. If the choice is only these options, A is better because it provides more space and is also probably cheaper. But I'm sure there are multiple other options which are better.

I feel voting would be aiding and abetting.

I see no windows on tha side of the house. That's a challenge. High fixed may work depending on what's next to your property on that side. The roof configeration for both plans could influence the choice. Do you have anything showing both roof plans?

"B" for sure, furniture can look strange with angles :-) Ds