Archons’ light radius should be a passive aura area-of-effect attack that causes strong light effects: potentially blinding normal monsters, hurting gremlins and undead, petrifying trolls, and so on.

Troll statues, including those created by petrification, can spontaneously unpetrify and become living trolls again. Possibly, this should be restricted only to rock trolls.

Merge Sunsword and Trollsbane like NetHack Fourk does (a single artifact that emits light, instakills gremlins and instapetrifies trolls, with bonuses to undead), except keep it a morning star and name it Sunflash (because a lot of these consolidated effects have nothing to do with trolls). Having it stay a morning star makes it an attractive choice for Priests, and raises the appeal of training morning star.

Trollsbane can be invoked to instapetrify all trolls in a radius of 5.

Cancelled trolls won’t rise from the dead.

Sunsword does extra damage to vampires and trolls, on top of its normal bonuses versus undead.

A troll killed by fiery or acidic means (including Fire Brand) cannot revive.

Chatting to trolls while hallucinating makes them appear to say internet-troll phrases: “Problem?” “U mad bro?” “Trololol!”

Ankh-Morpork levels in the Tourist quest should be populated with some peaceful humans, dwarves and trolls. However, the levels should also then avoid having lots of narrow corridors so it’s not incredibly frustrating to traverse them. (Or implement peaceful displacement).