According to CryTek on Facebook, lower textures were included "for optimisation
" <-- (I swear, with a smiley face). So for CryTek to release a high resolution texture pack, they would be releasing something that goes against the optimization principle. I dunno, but my money is on CryTek not releasing one at all.
This game should've been two DVD's. The textures included should've been at least 2 gigabytes alone, not a pathetic 400 megabytes. Even Unreal Tournament 3 had larger textures. And that game is ANCIENT.