This is a quick and simple one:
Total Paralysis normally requires you to strike the head (-5) of the target. This means it's only useful for casters with a solid DX or Brawling, or a very good Staff skill, vs. a poorly-skilled defender they really want as a prisoner. It's not particularly useful. It also mean's it's useless against creatures with Injury Tolerance (No Head), which isn't such a small group in fantasy games or when you're playing Ultima.
Instead, for my game, I'm removing the need to touch the head. Anywhere on the target is fine. Otherwise, the spell is as-written.
It would be amusing to make touching the head of the target even more useful - perhaps a penalty to resist. But generally location isn't worth including for all-or-nothing spells.
Additionally, Paralyze Limb works on the limb and extremities off of that limb, and works if you either hit the limb or the extremity.