I have a pedestal sink in my powder room and am replacing it with a vanity for storage. Even just a place for extra toilet paper would be great. But it also had no deck space even for a bottle of hand soap. My toilet/sink wall is 5-2, and we debated whether to use a 24 or 30 inch vanity. We decided the 24 would be better since I did not want the vanity right up against the wall. We also decided on an 18" deep vanity to keep it as small as possible, so not to overwhelm the space. And we opted to replace our toilet with a wall mounted toilet to make it seem more roomy. It will only project 21" from the wall. Your room is a little bigger, If you center the toilet on 34" of wall space (30" is minimum code, 36" is ideal), you will have 31" for a vanity, so you could easily do a 30" vanity. And there are some that come in sizes like 26 or 28.

After calculating what was written above me, it looks like you can fit the same size table I have in my dining room, which is 42" wide by 78" long with the leaf in. We can fit up to 8 people at our table with the leaf in. I also love having a rectangle table! I have two openings in my dining room - one to the living room and the other to the kitchen. I have a door on the other wall and a window on the 4th. Just place your table in the middle of the room and it will work.

I think smaller or same size, definitely wouldn’t go wider than the cabinet.

This would depend on your space and the size of the vanity. Do you have any pictures of the space or measurements that you can provide?