I'm repeating a number of ideas (some boring, some less so) than already mentioned here, but for my two-pennorth...
I tend to go with 5x5 rooms for everything, at the moment. If it gets used for a 3x3 workshop, I can place that centrally and use the 16 surrounding squares as at least temporary end-product storage (although it might be more efficient to make that the raw-material store, I know, if I have constant haulers rather than ones that work in spurts). I have tried to work in the Z-dimension for such things. Raw material stockpiles (and larger end-product ones) often also featured immediately above and/or below the workshop (though there is a need to walk to one side to find stairwells).
Corridors, I used to go with 1-wide, and enclosing four 5x5s (or a single 11x11) within a 'block' of streets, but recently have been turning to 3-wide corridors. And I can put nine 3x3s or 16 2x2s within that space, if I so want.
I've recently been rethinking my vertical (and diagonal) movement strategy, so that where I previously would have a 'framework' of vertical stairwells, alone, I've been workin with ramps. Especially since I've had room. There's two designs I've been toying with:
..#...#.....#.....#...#..
..#...#.....#.....#...#..
###...#############...###
..#...#.....#.....#...#..
..#...#.....#.....#...#..
..#...#.....#.....#...#..
..#...#.....#.....#...#..
..#...#.....#.....#...#..
###...###=#####=###...###
.........................
....X..v.......#^...X....
.........................
###...###=#####=###...###
..#...#.....#.....#...#..
..#...#.....#.....#...#..
or (subsampled)
..#...#.....#.....#...#..
..#...#.....#.....#...#..
###...###=#####=###...###
.......v.......#^........
....X...............X....
........^#.......v.......
###...#########=###...###
..#...#.....#.....#...#..
Note that I've put
both ends of a ramp-stack in the above examples, the true slice is as follows:
___X___v____________X____0
___X__#^v___________X____-1
___X___#^v__________X____-2
___X____#^v_________X____-3
___X_____#^v________X____-4
___X______#^v_______X____-5
___X_______#^v______X____-6
___X________#^v_____X____-7
___X_________#^v____X____-8
___X__________#^v___X____-9
___X___________#^___X____-10
... although if I have the vertical space, I wouldn't mind laying diagonals over diagonals, herringbone-pattern or otherwise.
Also, the side-of-corridor version (featuring opposing diagonals) means that at least some doors need around to different walls, or elsewhere (e.g. from north facing from western south-of-corridor room, seen to be filled in the subsample plan view).
But if I go for just a single ramp, I'd lay it out in a way to make it efficient for cross-zone travel, thusly... compressing the blocks down, and hoping it's still understandable:
Xv^X^vXv^X^vXv^X
vv.^ v ^ v.v^
^.^v ^ v ^^.v
X^vXv^X^vXv^X^vX
^ v^.^ v.^^ v
v ^.vv ^v.v ^
Xv^X^vXv^X^vXv^X
v ^ vvv^ v ^
^ v ^^^v ^ v
X^vXv^X^vXv^X^vX
^ v.^^ v^.^ v
v ^v.v ^.vv ^
Xv^X^vXv^X^vXv^X
v.v^ v ^ vv.^
^^.v ^ v ^.^v
X^vXv^X^vXv^X^vX
Note the adjacent (north-south, east-west and, across select 'blocks', diagonalNE-SW or SE-NW) ^ and v indicating direction of ramp. And even when using up the diagonal areas (which I might craft out as totally open, apart from ramp intrustions) this could easily be an area with 16x(2x2) blocks that would give 64 5x5 bedrooms, per level as well as possible things done within the 'spaces' of the diagonal cut-outs.
If it's a residential area (which I'd have single-product trade-good storage areas buffering from workshops and other noisy activites, well, except from the continual diggin-out of further levels of this area) it could house 64 5x5 bedrooms (or more 3x3s!) on one entire level, or if I worked vertically along one edge for the full 11 levels (0..-10) 132 separate rooms... Plenty enough for immigration waves, and giving a good selection of raw stone. (Read: a pain in the arse to shift out, but I put up with it). And the whole construction would be city-sized, with city-sized problems in management long before it became full!
But, I must admit, I've not yet gone to that extent, this is just an aesthetic ideal (if you like blocks of rooms, and or are The Borg), and I must admit that I always go more organic through sheer necessity, anyway, so while I'll have mapped out corridors and actually made raised platforms to let some rooms poke out the sides of inconveniently rounded hills, etc, there's always an environmental factor involved. Especially now that there's not so much unlimited digging space below the surface, before hitting 'inconvenient' voids. (Long before the definitely not convenient ones!)
Not counting 'special' parts of my fortress, e.g. the Trade Depot area and its defensively-equipped access tunnel (and/or above-ground construction).
Plus, for a while I did work a lot with towerblocks (blocks, indeed... they used an awful lot of stone ones, if I was strict about that!) with my "5x5 theme" mixed around a still mathematical relationship but a offset look...
#######
#.....#
#.....#
#.....#
#######.....#
#.....#.....#
#.....###.#########
#.....#.....#.....#
#.....#.....#.....#
#.....#...........#
#########.###.....#.....#
#.....#.....#.....#.....#
#.....#.....##.##############
#...........#...#.....#.....#
#.....#.......X.......#.....#
#.....#.....#...#...........#
##############.##.....#.....#
#.....#.....#.....#.....#
#.....#.....###.#########
#...........#.....#
#.....#.....#.....#
#.....#.....#.....#
##########.##.....#
#.....#.....#
#.....#######
#.....#
#.....#
#.....#
#######
That was giving four 'wings' of three-room 'suits': either for deserving dwarfs (bedroom, dining room, office) or doing something interesting with workshop interdependency, depending on the use I put the building to.
Having a different core size and room size makes for different layout, of course But I didn't use to mix and match in the same tower...
And, as already stated, building materials (block ones, at least) get consumed a lot. Although I often put large windows in, if I had enough glass as well...