Like the bath, the basin is another item that you should buy big. After all, you will probably use it for more than just splashing your face rinsing out tights, washing hair, fighting over the toothpaste, and so on. Whether you conceal pipes behind a pedestal or a syphon cover is a matter of personal preference. Pedestals look elegant, but have the disadvantage of.being at a fixed height. If you are tall and want a basin set higher than the standard, it would be better to do without the pedestal and set the basin into a cupboard top of unit (known prissily as a vanity unit) to whatever height is comfortable. Boxing-in unsightly pipes is made easier with a vanity unit. Make sure that wall-mounted designs are securely fixed to a load-bearing wall.
Check that any tap holes are in the position you want. As with baths it might be better to buy a basin without holes, and drill them on site. When positioning the basin, consider how high the taps will be you don't want to continually bang yourself on the forehead as you lean over to rinse out your mouth.
Be careful about contemporary, minimal designs. The Golden Age of sanitary ware design was the late 1900's and items from then have plenty of ergonomic lessons to teach us. A good basin should have areas to the side for siting the soap and tooth mugs, and they should drain freely into the bowl. Taps should be sited well back and the front lip should be as narrow as possible to prevent you from straining your back when leaning over.