birthstats.diff includes the stat breakdown in the second stat screen during character creation.
Pre-requisites: diff0811.zip/birth.diff diff1701.zip/birthday.diff diff1701.zip/xpf.diff
diff1701.zip/initgold.diff diff1701.zip/social.diff diff1701.zip/cleanup.diff diff0903.zip/birthsave.diff
diff0903.zip/birthskill.diff diff0903.zip/birthrand.diff diff0903.zip/amax.diff
diff0903.zip/tempfx.diff diff2105.zip/birthclean.diff diff2105.zip/birthextra.diff diff2105.zip/missiledam.diff diff0106.zip/birthextra2.diff diff0506.zip/equipmod.diff

(equipmod.diff defines equip_mod() (as required by birthstats.diff) without the rest of spoilmod.diff. It doesn't actually do anything.
Pre-requisites: None)

ignoreall2.diff replaces the "It cannot be harmed by foo." messages with "It can be harmed by foo." ones, and includes k_idx-based immunities as well as flag ones, thereby demonstrating that hard biscuits can't be harmed by elemental attacks. Which is good to know.
Pre-requisites: diff1701.zip/ignoreall.diff

questsee.diff causes the estimate of how many quest monsters are left to kill to depend on whether the player saw the monsters die. Killing the last one still ends the quest, but the quest counter doesn't know what an invisible monster was any more than the monster memory. This does, of course, mean changing the save file format, making this v4.1.4.
Pre-requisites: diff0811.zip/objknow.diff diff0811.zip/worthless.diff diff0412.zip/curse.diff diff1212.zip/curse.diff stormy.zip/stormy.diff diff1212.zip/bypass.diff diff1212.zip/autohaggle.diff dif1212.zip/dropspecial.diff diff1212.zip/saves.diff diff1512.zip/pseudoid.diff diff1512.zip/allart.diff diff1512.zip/moncol.diff diff1701.zip/artpower.diff diff1701.zip/spoiler.diff diff0903.zip/deathevent.diff diff0903.zip/plurals.diff diff0903/deatheventtext.diff diff0903.zip/wizmonster.diff diff2105.zip/curse2.diff diff2105.zip/deathevent2.diff

spoildam2.diff returns the "It gives you x more blows per turn." message to non-weapons (I forgot to restrict it to things which give the exact number of blows per turn).
?Pre-requisites: diff0811.zip/objknow.diff diff0811.zip/weapon.diff diff0811.zip/worthless.diff diff0412.zip/curse.diff stormy.zip/stormy.diff diff1212.zip/bypass.diff diff1212.zip/curse.diff diff1212.zip/autohaggle.diff diff1212.zip/saves.diff diff1512.zip/pseudoid.diff diff1512.zip/allart.diff diff1701/artpower.diff, diff1701.zip/spoiler.diff, diff0903/randpower.diff diff0903/fullident.diff diff0903.zip/spoilstat.diff diff0903.zip/tempfx.diff diff2105.zip/curse2.diff diff2105.zip/spoilstat2.diff diff2105.zip/missiledam.diff diff0106.zip/missiledam2.diff diff0106.zip/spoildam.diff*

*A rejected hunk in object1.c may need to be applied manually.

unident.diff moves the names of most objects to text files, in particular moving the unidentified ones to a file called u_info.txt, and enables unidentified objects to be edited within the % command. It uses both fixed names and the scroll name generator, although the use of the latter is very hard-coded (for instance, there's no easy way to create a second set of scrolls). This does,  mean that equippy characters are no longer displayed in shops.
Pre-requisites: stormy.zip/stormy.diff diff1212.zip/dropspecial.diff diff1512.zip/moncol.diff diff0903.zip/phial.diff diff0903.zip/deathevent.diff diff0903.zip/features.diff diff2105.zip/moncol2.diff diff0506.zip/randpower-x.diff*

* This patch should be applied beforehand and unapplied afterwards, as the flags it adds (which come from diff2105.zip/randpower2.diff) make no sense without further efforts. This is, however, safe to do. Also note that u_info.txt may need the V:* header to be changed to match the other ?_info.txt files.

--- Ideas ---

Put activations, wands, etc., on the "use" list.
Give the % fail rate in the character information.
Give the fail rate if you use the capital version of the use command.
Go through the character information screen as you edit your character with the wiz mode command.