Leave the wood and do a vessel sink - varnish, of course! My mother in law has a similar in her house and the wood top is one of my favorite thinks about it! ;)

"Things"

You can polyurethane it within an inch of it's life or paint it, but as the master vanity it will get the heaviest use. Chances are you wouldn't have found an in-stock top to fit and it doesn't have a fancy curve, so a custom top shouldn't be that expensive, and worth the cost to protect it.

A good tile person could tile the top,one with an artist eye. But, the grout joint is different from front to back, the tile is cut into a wedge shape. The piece doesn't look that large ,have you thought about finding a remnant piece of granite for the top.

As is usual, once the bathroom was ripped out, there was more mess underneath, so my budget has had to expand, and I am looking for places to cut costs. I did give some thought to trying the marine varnish, but trust me, there will be lots of water splashed around! It is 48" wide. The idea of using the dresser and tiling myself was to get solid wood and a custom look without spending a fortune. The alterations to the dresser and standard tiling are well within my abilities. Even remnant granite is going to up my costs if I have to hire it done. I can always use the dresser somewhere else and try to find another that is rectangular, but I do like this one!

It's a beautiful dressser, good luck!