IMO, the master bathroom is too small. 30" for a toilet (the minimum allowed) and 30" a vanity is tight even for a guest bath. Your closet is huge proportionally. I would take at least 2 feet from the closet to add to the toilet and vanity space (48" vanity and a 36" space for the toilet) because I would much rather be cramped in a closet than feel cramped in the bathroom. You could also take a few inches from the shower. 5' 34" showers are very common and plenty of room if you are not a large person.

I had the exact same problem. I picked out the vanity I wanted but did not think about the fact that it wasn't made to sit flush against the wall. I spent a month looking for something else, but in the end we decided to go with something shorter and have it not be against the wall. But we were going from 72" to 60" which is probably not workable in your mom's situation. I did find a lot of vanities that did have flat sides and could work in a corner, if you are willing to have the countertop fabricated. They just need to not have any trim detail on the top or bottom like the one you picked out does. I would just look at the ones without the pre-made tops. Because the pre-made top will still leave you with a slight gap because of the countertop overhang. This is an example: Avanity Modero which is sold everywhere, not just at Lowe's. The cabinet we ended up buying is an Avanity Madison which won't work for you, but I assume it is of similar quality. We are pretty happy with it. The drawers and doors have soft close but I do feel like the glides in my Ikea kitchen drawers are better quality. It is very pretty and I wanted a stained wood so I am really happy with our choice. If I had been willing to go with a painted finish, I think we might have stuck with the 72" Modero.

Do you like it? Hang it up. The number of people who will ever see it can be tallied on 2 hands. What possible dilemma could this be? It's your home; nobody on the internet is ever going to see it. This is a very simple decision that you can make on your own with no repercussions at all.

I would paint it this color.