I agree the vestibule/entryway is quite a small space, perhaps bigger would be more comfortable. The idea was not to take up to much garage space with this space since it is primarily there to meet fire code so that the upstairs attic egress is not directly through the garage (auto closing door etc...)
The garage doors we will be using are already purchased and are 9ft wide so unfortunately we are stuck there but then it begs the questions if we should not shrink the overall length of the garage some to better fit the doors.
Too many decisions.
What do you mean more exactly when you say a grand entry into the garage, please expound. This garage is still very much a work in progress.
We like to entertain in our garage spaces. The standalone garage/shop has a larger entry with covered porch and a 8 x 16 foyer so total space with porch is about 16 x 16. Great for meeting guests in good weather but poor when the wind is kicking up (along the Strait of Juan de Fuca). At the back of the shop is a large covered car port area where we can BBQ as needed for the gatherings. In this garage space, seating is set up for at least 32 people. (As an aside, the overall design of this space is for our future "live-in" care takers when we need this type of living assistance.)
The attached garage space is where we can comfortably seat 70+ people and also have ample room for serving tables. These are the reasons why the question was asked about intended use of your garage.
Further, there are no steps in these spaces. We wanted to be sure that access is always easy for us when we are more infirm and to reduce any trip hazards when we are older, and, in consideration of our guests as well. Know we can just roll up a garage door, but wanted all access points to be step free.
We have no understanding of how the proposed garage will be situated on your property and how it will relate to the house. Further, what views will the new garage have since it is assumed the property faces the ocean. Knowing full well, the garage door locations will be opposite from the prevailing winds, just hope that if views are available from the garage, they be taken advantage of. A garage with a great view is always a nice feature to have.
If the chance were available for me to do it over, would have added more space for entertaining while the cars are in their parking spots. (BTW, during the design process, we never considered entertaining in these spaces.)
Know the architecture from what my property holds is significantly different from your design, the above is simply some of my thoughts and the life style we enjoy with our collection of cars along with the area in which we live.
Positive you or your client will end up with a great place along the Pacific Coast.
Ody.