The most convenient rooms are ones that serve more than one function. The second most convenient rooms are ones that can serve the same function, twice.
Like this mudroom:
It serves the garage for your everyday arrival, but also serves the backyard. This way, any time you’re coming in from the outside all shoes get removed in the room that can handle a little extra dirt/water. No more wet shoes coming into your hardwood floors in the great room (or -gasp- carpet!).