I don't magic much, but as I understand it, the order of operations is Pick Spell --> Amp Up and/or Increase AoE --> Spell goes off --> Resist drain.
Why not just swap the spell going off and resisting drain? If the power of the spell renders you unconscious or dead, then it doesn't manifest.
Horrible idea. Player should be able to make a sacrifice play to save team. Knows going to die, so does a 9P fireball to clear out enemies. He fails Drain and dies, but saved team.
Or, know your limits and gamble on dumping your Edge into your soak pool to avoid dying.
And no, nuking a whole building as a "sacrifice play" should not be an option. If the amount of magic you're channeling is enough to kill you, it should just kill you. Do not pass go. Do not collect 200 nuyen. Do not do the thing. Just die. Maybe explode into glitter and mystical confetti.
Mages are already overpowered as it is, and being able to bring about an apocalyptic level event with the
chance of passing out or dying is ludicrous. No other character type has any options remotely as powerful, and for good reason. Street Sams don't get tactical nuke rocket launchers, Deckers don't have access to Ice-9, and Riggers don't get building-sized mechas, all because they don't scale with the intended power level of the game.
An Elf Aspected Magician who has focus in Sorcery can leave chargen with Magic 6, Sorcery 7, Willpower 5, and Charisma 8, and have a force 4 Power Focus. That would give them a base dice pool of 17 (5.7 hits) per attack, and a base drain pool of 13 (4.3 hits). Even if you Amp Up for 3, that's only 12 drain (not enough to kill you) on a Fireball. You would have to Amp Up for 10 or more to be lethal without edge use.
