Replying to several threads at once:
1. Most likely Wraith form will require non-JOAT points to cast. After all, they have made exceptions to the effects of JOAT before (Parrying & Bushido interaction, the resists from Resist Spells, etc.)
2. WarUltima: The notion that Mana Leech requires the target to HAVE mana is erroneous. The devs have REPEATEDLY pointed this out, and people still don't seem to hear it..
The "Leech" weapon properties give you whatever their multiplier is, times the damage you do, as points back - they have NEVER actually taken points from your opponent's mana pool, stamina pool, or Hit points (well, other than the damage you actually DO to them as HP). Mana leech is NOT a Mana Vampire spell - it just converts some of the damage the weapon does into mana for the wielder.
3. As long as the whammies have sufficient equipment on to maintain their forms, I don't see what any issue will be. After all, as one of you pointed out, enough Necro skill to cast Curse Weapon 100% & GM Spirit Speak are vital parts of the template, and means a more balanced template than "I'm gonna toss some equipment, cast, then remove all that and change to my combat suit" that is the soon-to-be-gone fake Sampire default (all the more reasons why I actually admire the rare true Sampires that did it without the gimp gear change).
4. Folks need to be a little more adventurous in their templates, anyways. How many of YOU, for example, have done a level 6 map solo with a melee warrior of any flavor (including the cartography & lockpicking, and without soulstone changes of skills)? I see all these people wanting to have the game made more easy, then pancake about the lack of challenges. If one would just look, they can MAKE their own challenges, simply by altering their characters. After all, on many non-online games, you often replay them with higher difficulty, for a better challenge - or with a less powerful character (or less powerful weapons, etc.) - be they fighting games like Street fighter or Mortal Kombat series, or combat/strategy games like Jagged Alliance II, Fallout or warcraft/starcraft (hell, even things like SimCity!).
You can do the same in UO, simply by going for the skill combinations less chosen - and might even find yourself having fun again...