I don't think two sinks are definitional in a master bath at all--while it's common to have two, plenty of master baths (including mine) only have one. So at a basic level, I don't think there's any particular reason you need to keep both if you don't use them both--doubly so in a "second master."

Personally I like your second plan better--I'd rather have a 42" vanity, and the space between the toilet and 36" looks tight. I wouldn't want carpet below a vanity regardless, so if you add the door you can change the whole thing to tile at the threshold. Then make the 36" space storage or a linen cabinet. I might even take down the wall between the toilet and 42" vanity if it's easy to do and have an open floor plan--I don't love the idea of a door that closes the toilet and tub off together.

I’d eliminate the small sink. A linen area would be great but would it make sense to give that space back to the bedroom?

Keep the wider vanity, remove the wall between it and the toilet, give the space with the other vanity back to the bedroom. From the perspective of the bedroom it must be strange to have that protruding wall.

Show the bathroom in relation to the bedroom with it's closets, door to the hall, etc.

IMO we need to see the whole floor plan not just the bathroom. I think the 2nd sink is not ideal and honestly I have never had a bathoor with 2 sinks in my life. I shared a bathroom with my sister for a few years until we got to a point where that was awful so our Dad made a 2nd bathoom . MY hubby and I have never needed t2 sinks in 60 yrs . I think a linen clset might work but I think that space is just kind of a waste . Is there a way to change the entry into the closet I never like a closet accessed from a bathroom

Thanks everyone for your comments. I should have showed the entire room.

It's not exactly to scale obviously but the 2nd vanity area does not stick out like the first picture made it seem like. It's quite a large room so I don't think the bedroom needs any more space. I considered open shelving in there or linen closet. I really like the idea of removing that wall between toilet and larger vanity. But unfortunately cost may have to win out this time. I'm not sure we have it in the budget to do the wall and flooring and larger vanity. I'm not exactly sure yet on price difference but will find out.

If we have to remove larger vanity bc of cost...any suggestions on what to use that space for? I've thought about a full length mirror or a piece of furniture like an armoir. Anyone have any more creative ideas?

Oh, and is it preferable to have closets open to bedroom rather than bathroom??

THANKS AGAIN!!