I have to agree. Liches of all kinds have been the quintessential magical BBEG in a large portion of P&P games, yet are strangely absent from the games that are meant to emulate the experience of playing a session of whatever high fantasy P&P you prefer.
Personally, I've never understood this. Liches, after all, can be so much more than just undead spellcasters. From the Tomb of Horrors' Acererak to more straightforward power-hungry necromancer who finds immortality through his obscene and wretched rituals, to bardic Bach-playing perfectionists who sought an eternity to pracice their art (listen to Toccata and Fugue in D Minor and tell me that ****'s not lich as ****).
Hell, some of the most interesting wizard antagonists inevitably end up as liches. It's one of the few ways to justify their immense power.
There are a lot of ways the whole "souls are power" thing could be integrated with the core concept of a lich. One good idea I heard was, essentially, the lich being more of a puppet master. The soul residing in an unaging object, directing the actions of its body from far away.
Probably undoable at this point, since that would probably be some kind of micromanaging system where you'd control the PC's physical body and have it distinct from the PC him/herself, which is obviously a stretch at this point in the funding process.
Regardless, a reimagining of liches, the lynchpin of many a D&D campaign, would definitely be a cool thing to see.
