There is a specific kind of chaos that happens by the front door around 8am, when everyone is leaving at once and someone is patting down their pockets asking who had the car keys last. A key box by the door ends that argument for good. You walk in, you hang up, you walk out knowing exactly where to look, and that small bit of order tends to spread to the rest of the entryway without you doing anything else.
For finishes, go plain before you go pretty. Black and white are the easiest to live with because they disappear into most hallway colors instead of fighting the wallpaper or the paint you did three years ago and have since forgotten the name of. Wood look ones, the pale oak style especially, suit entryways that already lean warm, with a bench or a console nearby. If you want a bit of personality, a patterned or painted box can work, but it will read as a feature, so only pick one if your hallway can take a feature without feeling cluttered. If you own none of this and want a single starting point, get a basic box with a handful of hooks and a small shelf or tray on top for post and sunglasses. That combination covers almost every household without needing a second thing bolted on beside it.
On placement and size, measure the actual wall space you have, not the space you wish you had. A box with eight hooks sounds generous until you remember everyone in the house has a set of house keys, a car fob, a work pass and sometimes a bike lock key, and suddenly eight is tight for a family of four. Leave at least a hand's width of clear wall above and below so it does not look jammed between a light switch and a mirror. Small apartments and rental hallways do better with a narrower, taller box mounted at eye level near the door rather than a wide one that eats half the entry wall. Houses with a mudroom or a wider hallway can go bigger and treat it as part of the furniture, not just a hook rail with ambitions. The mistake people make most is mounting it too low, at a height that suited them and nobody else in the household, so check it works for the tallest and shortest person using it before you drill anything.
Whatever is on either side of your front door, a key box gives it a job.