It would be great if everyone had a dedicated mud room. Some homes are not large enough for one so lets see if we can come up with some ideas for those.
I would recommend a rear hallway that every family member uses regularly. 4-5 feet minimum in width - you really don't want things "sticking out" in the walkway.
If you have a staircase in the hall, use the area under the stairs to create a “drop zone” without taking up any extra room. A wooden or metal bench is a great addition (if you have the room) to allow someone to remove shoes for storage. I would allow at least one hook and one shelf per household member for their own personal drop zone. Include an outlet or two for charging the electronics and cell phones we all have.
I love to use a "built-in" locker design, when I have the chance, in our house plans. They don't take up a lot of room and you have an organized way of controlling clutter.
Flooring needs to be something easy to clean and be durable. Stained concrete or brick pavers would be a great flooring option for this area. Tile would be durable but you really need to seal the grout well in this area.
These ideas are not rocket science but I hope they get you looking at your space in a new light. Use your imagination and enjoy your new found storage space!