When the game auto-saves a fortress, it creates a filename with the following format: "<region>-<season>-<year>". My request is that the season and year portions be swapped, and that the season portion be replaced by the month number. Currently a lexical ordering of these folders does not result in a chronological order, but the two changes above would (in most cases).
The few cases where it would not are due to there being no leading zero on the numerical bits. Year 99 would come before year 100, for example. But if it were formatted 099 instead, everything would be fine. How many leading zeros would be needed is subjective, but I would guess that 5 digits for the year would be plenty for nearly everyone, and 4 might be good enough. The month would obviously need to be 2 digits, unless instead of a month number, a season number was used.
I'd also like this leading zero to be extended to the region number as well. Instead of creating region1 through region 9, and then jumping to region10, start with region01 or even region001. When generating new worlds and then choosing Start Playing, it is much easier to just hit the up arrow once and immediate arrive at the last world generated. But as it is currently arranged, this works only for the first 9 worlds generated, at which point I have to delete all the worlds, and then start again. I'd rather keep generating and checking until I find a good world, and then delete all the other worlds in one go.
I suppose these are really minor problems, but the fix should be excessively easy as well (assuming there are no arguments against it that I haven't thought of), so it balances out.