1. Each class is a specialist occupation; that is, you do mainly one thing, and you should aim to do it very well.
2. Your overall equipment gathering strategy should hence aim to improve your one speciality.
3. The converse of the above assumption is that you should not seek out equipment that ameliorates the things you do not do well.
4. There are only three classes you should consider heroing on; mage, thief and warrior.
5. As a hero, all your statistics are maximised.
6. Despite the fact that are many forms of saving versus equipment in the game, it does not come in large enough amounts per piece of equipment to justify trying to protect yourself against all forms of magical attack. Since saving versus spell is the most common, you should only be concerned with this form of equipment.
7. Whilst saving versus spell can reduce the amount of damage inflicted by magical attacks, it's key strategic value lies in enabling the player to avoid a compromise of their ability to inflict damage.
8. Like most things, the law of diminishing returns apply to these formulas. At some point, one should not trade off one's primary statistic for any amount of secondary statistics (at least within the limits of equipment generated by the game).
9. These assumptions only apply to heroes, and to those players 2 or 3 levels away from hero status.

Assumptions specific to warrior heroes:

1. A warrior's speciality is inflicting damage by physical means.
2. The key statistic is therefore damroll.
3. Your equipment gathering strategy should seek to maximise your damroll.
4. In order to inflict damage, you must hit your target. Therefore, hitroll is of concern
5. However, warriors innately have a large THACO, therefore hitroll is of less concern
6. Warriors can still inflict reasonable amounts of damage even when blinded, therefore saving versus equipment is of little value. The warrior class is also the most vulnerable to spells, therefore, there is little value in trying to ameliorate this vulnerability, since saving versus spell equipment does not come in sufficient amounts per piece of equipment.
7. A warrior's AC reduces per level, and spells lower it further, therefore AC equipment is of little value.
8. Warriors innately have many hitpoints, therefore hitpoint equipment is of little value.
9. A warrior's main damage amelioration strategy is simply to kill your enemy before it can inflict damage on you. This means backstabbing is of crucial importance.
10. Warriors only need mana for personal preparation spells, therefore mana equipment is of moderate to little concern.

Assumptions specific to mage heroes:

1. A mage's specialty is inflicting damage by magical means.
2. The key statistic is therefore mana.
3. Your equipment gathering strategy should seek to maximise your mana.
4. Mages hit like little girls. Therefore, neither hitroll nor damroll is of any concern to a mage.
5. A mage's effectiveness is reduced if blinded, therefore saving versus spells equipment is of moderate concern. Additionally, the mage class is least vulnerable to spell effects, so it is possible to significantly reduce these effects with just a few saving versus spell items.
6. A mage innately has few hitpoints
7. A mage's AC can be lowered significantly by spells
8. A mage hero will possess the skill of dodge
9. Your main damage amelioration strategy should be to simply not get hit.
10. Therefore, AC equipment is moderately more important than hitpoint equipment.

Assumptions specific to thieves:

1. There is only one thing that thieves do better than any other class, and that is backstabbing.
2. However, this a thief's only special ability. Warriors have two, lowering AC per level, and critical hits during combat. Mages have three, mana back per kill, manashield, stone skin without loss of movement points. Therefore thieves need to be maximise their ability to backstab.
3. This means maximising hitroll and damroll. Since thieves don't have a particularly outstanding THACO, hitroll is of moderate concern, while damroll is of primary concern.
4. Your damage amelioration strategy is that of the warrior. Dodge is no particular advantage, since both the mage and the warrior will also possess that skill.
5. Since a thief's AC does not reduce per level, this places the thief in something of a dilemma. Should AC equipment be used to ameliorate this weakness, or should extra damroll be used? Since assumption 4 states that a thief's damage amelioration strategy should be that of the warrior's, extra damroll should be used.
6. There are not enough equipment slots to compensate for a thief's lower hitpoints vis-a-vis a warrior, therefore this should not even be attempted. Hitpoint equipment is therefore of little value.
7. Thieves have a lower vunerability to the effects of spells vis-a-vis warriors, therefore saving versus spell equipment is of moderate value, since it is possible to significantly ameliorate spell effects.
8. Thieves also have the mana resources to use it for combat purposes as well as personal preparation, therefore mana equipment is of moderate value to the thief.

Conclusion and Summary
A note of warning. The way I've expressed these formulas implies that all quantities are equivalent. Clearly this is not the case. It would be sheer insanity for a thief to sacrifice -3ss to gain a mere 7 point reduction in their AC. The first statistic in the figure (reading from left to right) is the primary statistic for that class. The other figures are the secondary statistics, reducing in importance for that class the further to the right they are. Each number should be treated as the equivalent for a unit of primary statistic, that is, the quantity of secondary statistic for which you should be prepared to sacrifice a unit of your primary statistic.