I like satin in a bathroom and always use Benjamin Moore. Maybe speak to the paint consultant to discuss characteristics, if still unsure.

There isn't just one answer! I like Benjamin Moore Aura, Bath & Spa in matte. Some people like eggshell for bathrooms. The most important thing is an exhaust fan that is sized properly and vents to the outside. Get a switch timer, so the fan runs for at least 30 minutes after someone has finished showering.