I would not put a double sink vanity in a single family bathroom unless you think that 2 persons would be there at the same time (without being in the shower or toilet of course) often enough to sacrifice this space for a full height cabinet that gives you a lot of storage. Also I see that you have a little girl. It will take her forever to be able to wash her hands without the use of a stool if you put vessel sinks. I am 5'2" and I was at my brother house one day trying to apply mascara in his bathroom. As soon as I get closer to the mirror my breast was touching the edge of the sink. It is not the end of the world but if there is water in that area, my clothes would get wet. I would put one good size single sink vanity with a full storage beside it.

As for extending the counter top, I would instead use a rolling storage unit. It gives you some more storage and a little bit of a flat surface. You can put a bin in the last drawer and use it as the garbage can. That would be an inexpensive solution until you are ready to move the W/D:

https://www.amazon.ca/Shozafia-Rolling-Storage-Organizer-Kitchen/dp/B07D1M5DQD

https://www.wayfair.ca/storage-organization/pdp/rebrilliant-6-drawer-rolling-storage-chest-rebr3336.html

Wait till you’re ready to move the laundry machines. Then you have the room for a true double sink and vanity. I would not use vessel sinks. They create more splashing and for shorter folks, they’re obnoxious. Use under mount rectangular sinks. They have a clean modern look. Use @suzanne_m’s idea of a rolling cart for now. After your big renovation it will still be useful.