As for the lich the main credit goes to the CPR for the model and textures and i havent done much work upon it.I also have one idea for this if someone can create retextures for it perhaps we may get the so -called unmentioned in lore -Elemental Liches,the default one can be a Frost Lich.
Piracy Mod??Link?
GIANTS Mod by the Puma Man, or w/e his name is, is considered as a Piracy Mod since he took creatures that were created by other people or were from another game and just threw them all into one big mod. It is kinda nice cause there are some good ones I like in it but majority of this mod is really crap. The giants in this mod are crap.. Really just Giant-Nords with new voices.
Also, as for the Liches. Can you make the tradition Nether Lich, Lich, and Ancient Lich first? That will only require two different models since Liches and Ancient Liches can look the same while Nether Liches is basicly a more ghostly version of the normal Liches, as shown in Oblivion.
~Edit~
That Lich you have can be a Nether Lich easily, if you ask me. Just add a staff to his right hand as part of the model (Like how the this Giant's Club is part of his Model)