Mana leech required to support Vengeance

Additionally, I calculated the amount of mana leech that is required to support Vengeance. I assumed the following:
1. Baranar's Star (147 avg. dmg) or a 100 dmg weapon
2. 168 Strength
3. 90% chance to hit
4. Hell difficulty = 50% physical resistance and 1/2 leech
5. Target is not immune to physical damage
6. Level 28 vengeance (10.7 mana cost)

Without Fanaticism and might merc (= only conviction), a paladin needs the following amounts of mana leech to support Vengeance:
- Baranar's Star: 13% mana leech
- 100 dmg weapon: 18% mana leech

Using level 26 Fanaticism reduces the need of mana leech to:
- Baranar's Star: 5%
- 100 dmg weapons: 7%

Might Mercenary (level 22 Might at merc level 75) reduces the need in the following way:
- Baranar's Star: 7% mana leech
- 100 dmg weapon: 10% mana leech

With both level 26 fanaticism and level 22 might, we get the following figures:
- Baranar's Star: 4% mana leech
- 100 dmg weapon: 5% mana leech

It seems that you have to really take care that you leech enough mana back with Vengeance. Mana is not a problem with Zeal, because it costs only 2 mana per 5 swings, and it is mostly used with Fanaticism or Concentration. Thus, zealots may do well with only minimal mana leech, while avengers must pay a lot of attention to it.

Thankfully, many good items such as Tal Rasha's Horadric Crest and Vampire Gaze have lots of leech. Zealots, on the other hand, may use items like Harlequin Crest, which have no leech at all, and rely on some minimal mana leech on one of their items.