Here are more spells from GURPS Magic I'm revising, or have revised, in my game. This is based on a "You can't be right about that" moment in my last game session.
Shocking Touch and Burning Touch are melee spells that I think have some issues.
Shocking Touch bypasses all armor; only natural DR helps. Metal armor, leather armor, suits of cloth, +5 insulation, whatever - bypassed. Weird. Lightning doesn't do that. Lightning Weapon doesn't do that. Also, unlike Lightning, while it can short electronics it can't do a Surge and stunning. Also weird. Not only that, while lightning attacks generally do less damage than other direct-damage spells, this one does more than other direct damage spells with more additional effects as well.
Burning Touch bypasses all armor, too, for reasons I can't fathom either. Uhm, to match Deathtouch? It's probably enough that it's fire, although juicing it up wouldn't hurt. It does burning, same as Shocking Touch, with no noted effects aside from (like all burning attacks) setting things on fire.
Here is what I did to clear up that weirdness.
Deathtouch - works as listed. It does 1d toxic per energy, bypasses all DR on the subjects it works on, which includes undead even though they're usually able to ignore toxic damage. If questions come up, I will base the answers on "what would Toxic attacks do here?"
Burning Touch - does 1d+1 burning (up from 1d) per energy. Can set fires normally.
Shocking Touch - does 1d burning (down from 1d+1) per energy, plus the surge/stunning effects from the lightning spell. Stunning effect as per lightning. Armor, aside from metal armor, protects normally. Metal armor only provides DR 1.
I think this is a good way to go - Shocking Touch is great against metal armor and can stun, Burning Touch can roast you but it's a more-or-less straight up fire attack (and they usually do pretty good basic damage), and Deathtouch is the bypass all DR toxic killer it's meant to be.
I've done a lot of little cleanup actions like this one. It's the kind of revision to GURPS Magic I'd like to see - but I'm unlikely to do. Lots of people really dislike the system (but have opinions on how to change it), use Ritual Path Magic instead (but have opinions on how to change spell-based magic), or have a very different idea than I do on what constitutes a "fix." But in my games, at least, I get to do what I want to do. It's mostly cleaning up exceptions and merging spells and eliminating oddness.