Some way to make riding effective in the endgame (mainly addressing the problem that no steed can wear an amulet of reflection and usually dies to too much HP damage from ray attacks). This could be an artifact saddle that either gives your steed reflection or makes monsters focus only on the rider, or simply have the player’s reflection extend to their steed similar to how magic resistance does.

If you chat to the Oracle while carrying invocation artifacts (or possibly just after you’ve triggered the game flags for having acquired them at some point) she offers you a special consultation which helps show an unspoiled player the next step to take to complete the game, given what you have so far.

Pets’ closeness to the player should correlate with higher tameness, so that if you’d prefer it stay a little farther away you can deliberately decrease its tameness or vice versa.

When you read a magic marker, instead of a single fixed string, it gives a monster-based pigment. E.g. “Cockatrice Yellow”, “Hell Hound Red”, “Gremlin Green”.

Artifact leash that always makes the pet it’s attached to slightly faster than the player so that it won’t lag behind.

Add an option that makes you begin the game with all weapons dropped on the floor. This is to prevent you ever wielding a weapon so you can’t break weaponless.

Make the Magic Mirror of Merlin give slotless reflection instead of magic resistance; this is more thematic and makes for more interesting strategy.

Change the Knight quest artifact to be the Holy Grail. When quaffed from, something good happens; perhaps it needs to have charges or invoking it fills it up so you can drink from it (and you don’t have to drink from it immediately, allowing strategic choices). Should give magic resistance when carried. Possibly gives the effect of a random potion when quaffed: always a “good” potion when blessed, a random one if uncursed, and a “bad” potion if cursed. Or it blesses items dipped into it.

If you ascend with your alignment mismatching your align0 (meaning you changed alignment at some point), your game-end reason is recorded as “ascended in dishonor”.