Focus on functionality first. Would the bigger vanity make daily life better? Worry about the look of a feature wall after you’ve nailed down usability.

I don’t think we need a double vanity there. We are just considering that in case we decide to sell the house in the future.

I attached four different scenarios. In three the layout is the same only the vanity size is different. 1500 mm double and 1200mm and 90mm single

I would keep the similar set up as original. 1500mm vanity. You have the plumbing already. So use that. You don't have to physically use both basins, but the next person may want to.

You really need to draw all pieces to scale. What size shower. 1200x900 or larger? Are you replacing the shower completely?

Shower is 110*80. We are gonna get a new shower screen so we have flexibility to change the shower screen

these options have variations including double vanity (from 1500-1800wide), shower (1200 x 1500 wide) and big bath (up to 1800 long) and if you plan to add new tiles the new locations of the fixtures shouldn't add dramatically to the costs but the different options show how some arrangements included reachable wall space for towel rails and standing rooms that doesn't leave a wet puddle on the floor in front of the vanity and comfortable cleaning access around the bath and the feature wall should be added after the fixtures have been located..

Thank you all for great ideas. My preference is installing a 1500 mm wall mounted vanity. If that's too big for the space I have I will do with a 1200mm single vanity. If I want to go with the right bottom or left bottom layouts in @oklouise comment, how close the vanity can be to the wall to still look nice and be functional and easy to maintain? given that the length of that wall is about 2m. should I leave 50mm distance to the wall or I can leave 25mm from the wall and 25mm fromthe door and install the vanity in the middle.

@oklouise Thank you so much for drawing up those ideas.

with 2m of wall space you could easily fit in a vanity up to 1.5m wide and 10cm from the corner is a perfect space to hang a hairdryer but make sure you discuss relocating fixtures with your plumber as other options could provide more wall and floor space and a nicer view from the entry door.

Why can't you put the vanity right up against the corner of the vanity wall. You have said the wall is 2000mm long. There is plenty of room for a 1500mm to 1800mm double vanity. If you leave a 250mm or 100mm gap from wall, that is just a collection point for dust and grime, that will be difficult for cleaning.

by "other options" i mean that you should consider all other options for locations of fixtures..there is already plumbing along each wall so swapping the location of shower and bath or vanity isn't as challenging as if there were no original plumbing in that area and if you plan to replace the fixtures and tiles rearranging the fixtures will only be a small percentage of the budget and it's a shame to limit the final result without at least considering other options..and although there is enough space to have the vanity hard up against the wall my suggestion is to have the vanity away from the wall to make it easier to clean and also because the small nook is an ideal space for hanging a hair dryer and with the luxury of so much space it will be easier to install a vanity away from the wall

I would move door to centre of the wall and put bath and shower down one side and db vanity down other. Simple and very generous. Window onto vanity, blade of glass for walk in shower on ext wall, free standing bath and door opening back onto bath. Would look fab! Margot