I mentioned in the post about mapping towns that historic "city blocks" seem to be around 200 to 300 yards or so, about 1/5th of a mile. According to Ancient Town Planning, each block typically had four or five buildings. That leads to the idea I've suggested before: randomly define building placement in a block by rolling a d6 with pips, with each pip representing a building. Actually, I guess this would be the definition of each *corner* of a block, since the intended meaning is probably four or five building fronts on each side of a block, an arrangement that's still pretty true today.
But there's a problem with rolling for the layout of every block: it's too much die-rolling. It would be too tedious to roll for the building layout of every block, and to map out every block at the 30 yards per hex or square scale. It would be a tremendous waste of paper or disk space and a tremendous waste of time, since most of the mapped area would either never be used, or used once and ignored forever after. JD Jarvis has been doing some town geomorphs lately that would greatly simplify this, but you'd still need to keep notes about which geomorph pattern to use where, and there's still plenty of room to lose track of where the party is supposed to be.
So, I'm going to turn back to one of my principles: only describe differences. Assume first that there's a unit above the block level called the neighborhood. Each neighborhood is either one quarter or a part of a quarter, depending on whether we're talking about a village or something bigger. Most of the blocks in a neighborhood are going to be pretty much the same, and similarly most neighborhoods in a given quarter are going to be pretty much the same; the main differences are going to be between quarters and between richer and poorer neighborhoods within a quarter. Each neighborhood, however, may have one or two blocks that are unique compared to other blocks in the neighborhood.
So, just roll once per quarter and record that block arrangement as the default. Roll 4d6 for the common quarter and read the results left to right as the layout of each corner of a block, starting with the northeast corner and moving clockwise. Thus, if you roll 1 3 3 6 for the common corner, the default block arrangement is one large building in the northeast corner, a row of three ordinary building in the southeast, three ordinary building in the southwest, and a double row of three buildings each in the northwest (with the second row facing an alley.)
Draw a map of this standard block. Each city or culture can have its own style by deciding whether there are alleys between each dot or the buildings share a party wall, or whether the dots represent just buildings or houses surrounded by walled courtyards or buildings with internal courtyards. Even building styles can be noted ("Two-story buildings abutting street, second story juts out over street.") You could do this in the one page dungeon format, mentioning layout style and building style to the side of the map; you could even do two blocks on one page or two pages per quarter, distinguishing residential and commercial blocks in the same quarter.
Repeat for the craftsman quarter. Roll only one die for the noble quarter, since the rich are going to have bigger houses and thus fewer buildings per block. For the specialty quarter, roll four dice, two dice (north and south ends of block,) or just one die, depending on what the specialty is; a temple district might have blocks that resemble the noble quarter, while a seaman's district would be more like the common quarter. You now have either four or eight pages describing the basic layout of your town, possibly more if you break down any quarter into two or three major districts. You really only need to refer to these maps when the players decide to do something unusual, like raid a shop or defend a tenement against zombies.
Now, decide whether there are any significantly different buildings or public spaces you absolutely need to map, like city hall or a market square or the founder's mausoleum. Roll separately for the block layout of each of these, if you don't have any special ideas. Draw individual maps for each area and decide where these landmark blocks would be in the town.
There will be at least one non-standard block per neighborhood. Just assume that the non-standard block won't be dead center in the neighborhood, but one block away; roll a d8 or d12 for the direction, and note that on the page for that quarter or that neighborhood. Whenever the players have a reason to go to that block, or whenever in-game events demand a unique block layout, roll the d6s for the block layout and draw up a unique map.