Counter top basins are highly recommended in this setting, and the look out for extremely unusual decorated designs. Place it on a washstand or run-down vanity unit. Add unique ornaments and antique framed mirrors.
The ultimate luxury in a fantasy bathroom would have to be a waterproof TV. You could even think of doubling the bathroom up as gym, complete with exercise bike and rowing machine. Ornaments should be unobtrusive, so choose things like small piles of pebbles and modern wall prints over candles and nick-nacks.
Materials. Look for bathroom basins made from quality materials. You don't want anything that will be easily damaged. Scratches can make it look old and dingy so get something that is highly resistant to scratching. This will keep it looking like new for years to come and you will appreciate the way it prolongs the value of your investment.