Here is another spell I revised/tweaked/changed for my personal DF game.
So we have a wizard in my game who uses zombies and the Zombie spell. He'd like to get Mass Zombie but it requires Charisma 2+.
I get why - it's at least partly a legacy issue. Way, way, way back when that spell rolled out, it required Charisma 2+ or Strong Will 2+. But Strong Will 2 has no meaning in 4th edition GURPS, since Will is a secondary characteristic and not just your IQ plus or minus the effects of advantages. Therefore that got axed.
What we're left with is a spell most useful for misanthropic people-hating skeleton-loving death wizards but only likeable ones can learn it. Amusing to no end, but I'd like an alternative that doesn't involve Shortcut to Power. Or involve using a specific template (or Deathliness, DF9, p. 15) in order to have wizards with Mass Zombie.
Lucky for us, there is a way out - Talents. The Thanatologist (PU3, p. 16) talent has the right combination of cost (5/level, same as Charisma), effect (bonuses to mostly death-related skills), and flavor.*
As written, except:
Prerequisites: Zombie and either Charisma 2+ or Thanatologist 2+ (See Power-Ups 3, p. 16)
And that's that. Wizards and Evil Clerics and Unholy Warriors can add Thanatologist to their list of Power-Ups. Limit 4 levels.
* Just as an aside, it's worth considering if the alternate benefit of that talent - the bonus to certain Fright Checks - is worth trading back out for the reaction bonuses. Which fits better - the death-focused wizard is less frightened by scary undead? Or the scary undead like the wizard better? Tough call, and one I'm not prepared to make without talking to my players face-to-face. After all, they're both logical effects - "Ghosts love Gerry! He should talk to them." and "Everyone make a Fright Check from seeing the zombie spewing maggots all over Hjalmarr! Gerry gets a +2, it's nothing he hadn't seen before from the Lunch Lady Zombie from the Black College." Both would be too much, I think, unless you halved them (+1 to each per 2 levels.)