Currently, I typically use the following:
Top: Farming layer, trade layer, large general storage (non-stone, non-ammo, nonwood, etc).
Z=Top-1: Crafting layer. A + shape layer with individual 5x5 crafting rooms jutting off from it. Occasionally has farming as well, depending on terrain (current one has a small strawberry farm on this level, using the trick to let you grow them underground).
Z=Top-2: Smelting/furnace layer. A + shape layer with several huge bar storage rooms for storing metal and charcoal bars, and many smelters/furnaces of various kinds.
Z=Top-3: Initial/noble's housing. A + shape, with a kitchen on the west wing (primary food storage to the west of that), and three arms jutting from that with either 3x3 or 3x5 rooms depending on the value the person has to me. I usually put a legendary dining hall between the staircase and the kitchen/food storage. Rooms have a minimum of 2xstorage (G), bed (B), table (T), chair (C), and 4xstatues (S).
O---O
|SBS|
|GCG|
|STS|
O-D-O
Z=Top-4: Barracks, commons housing. A + shape, with a barracks on the east wing, and three arms jutting from that with either 3x3 or 3x5 rooms depending on the value the person has to me. Rooms have 2xstorage (G), bed (B), table (T), chair (C), and 4xstatues (S).
O---O
|SBS|
|GCG|
|STS|
O-D-O
Z=Top-5: Immigrant housing. A windmill shape, with lots of 1x3 rooms jutting from its arms. Rooms have storage, bed, and table.
Z=Top-6: Mausoleum. A few 3x3 or 5x5 rooms for nobles, but mostly a large commons room.
Z=Top-7: More Barracks, another food storage for the (two or three) barracks on this level.
Z=Top-8: Hospital. Placed low so that anyone suffering from an attack by a cavern beast can be put in here quickly. My dwarves have a remarkably low rate of injury on the surface.
At least that's how it is ideally. Not how it always goes, sometimes I need something else NAO so I build that instead and push another layer down further, or push things on the same level.