We finished our remodel except for a mirror over the sink and a recessed medicine cabinet on a corner wall... Thought I would post some photos of how,the vessel sink turned out installed recessed as an apron-front sink. The guy doing the remodel used local cabinet shop to fabricate the center 2-door vanity section to accomodate the install, added a stronger bottom shelf for the sink to rest on and cut the normal front stile to fill in the front opening... We used a remnant of Cambria Oakmoor Quartz with gray shadings vs the usual tan for countertop, a bench top in the tub/shower, and the niche bottoms. Found it at the fabricators our contractor favors and they were very good to work with. Pencil edges on all pieces but the tub bench...that is demi bullnose. Tub alcove and wall under window used the DalTile Modern Dimensions white matte 4x12 subway tile w/Florida Tile Bliss Iceland in niche backs. Moen Rothbury chrome single lever faucet for sink and tub/shower. Toilet is AS Town Square toilet, Princeton tub 30x60, and the AS Loft vessel sink... Vanity hardware Milan 6" in chrome...flooring is LVT click install from ProSource--Resista H2O--waterproof...in kind of driftwood gray, fairly uniform Went with a vibrant coral for the walls --SW Coral Reef--made up in Benjamin Moore eggshell and used in the linen closet walls as well. Trim is Super White. Electricians add added a Panasonic exhaust fan with heater/no light--because of joist spacing. Light fixture is from Wayfarer..I wanted a 4 but husband wanted a 3. There is a can in the tub alcove...both lights on dimmers. added a double outlet on corner left of the sink and an outlet behind the vanity, available inside second drawer on right.

Apologies if you have already considered this, but with a shelf vanity, if the sink does not sit on top of the shelf, then the sink will start at the counter, and go below the shelf. Its a design consideration (your right hand photo shows it ) -- what do you want visible -- plumbing wise. The depth of the vanity shelf front may need to be adjusted so that the bottom of the sink and the plumbing does not show, or plumbing is selected that is attractive. The cottage-y example has a deeper front on it to hide the sink bottoms. Benjesbride has an excellent point about keeping stuff on shelves clean -- it will take a lot of cleaning to not continually collect dust (it'll show on the shelving, and be embedded in the towels...dust, splashes, etc.). Good luck!

Deeper, wider sinks https://www.us.kohler.com/us/Ladena-20-7-8-X-14-3-8-X-8-1-8-undermount-bathroom-sink/productDetail/bathroom-sinks/417487.htm?skuId=343755&brandId=429839 https://www.us.kohler.com/us/Ladena-23-1-4-x-16-1-4-x-8-1-8-undermount-bathroom-sink/productDetail/bathroom-sinks/417491.htm?skuId=363138&brandId=429839

I think it would look great. There are a lot of examples if you google undermount bathroom vanity. https://www.homedepot.com/p/MR-Direct-Undermount-Porcelain-Bathroom-Sink-in-White-U1611-W/311963081 They do make less deep vanities. This is 18.5" deep and has 2 colors and many widths. https://www.homedepot.com/p/Home-Decorators-Collection-Maywell-30-in-W-x-18-5-in-D-x-34-4-in-H-Bath-Vanity-Cabinet-Only-in-Blue-HD2030P1O42-BU/314144506 You can also find them with the tops and sinks already done. https://www.homedepot.com/p/Glacier-Bay-Everdean-30-50-in-W-x-18-75-in-D-Bath-Vanity-in-White-with-Cultured-Marble-Vanity-Top-in-White-with-White-Basin-EV30P2-WH/311606054 https://www.homedepot.com/p/Glacier-Bay-Delridge-30-in-W-x-19-in-D-Bath-Vanity-in-Pearl-Gray-with-Cultured-Marble-Vanity-Top-in-White-with-White-Sink-DR30P2-PG/310163643 https://www.homedepot.com/p/Glacier-Bay-Modular-30-1-2-in-W-Bath-Vanity-in-White-with-Solid-Surface-Technology-Vanity-Top-in-Silver-Fox-with-White-Basin-PPDEC30-WHT/308411271