Actually clerics cast remove fear, I think it's better to cast resist fear before a battle so you don't waste time trying to remove it during a battle when you could be meleeing. Plus mirror image is a really ordinary spell, since your mage shouldn't really be targeted if you're not soloing.
I thought fireball because you had web and web's only good if you follow it up with an area effect spell since your own party will get caught in it.
There aren't really that many summoned creatures so death spell IMO is superfluous if you're a sorceror and limited on spells. True, if you've got Keldorn he can true sight but I still stick with improved haste. This is a must have for me.
Mordenkainen's sword isn't for killing, it's for distracting (this will be very useful in ToB), because hardly any enemy will be able to damage it since it needs a +4 weapon to hit it. I don't like finger of death because anyone you really need to kill with it won't fail the save so they won't die, and the damage it does instead isn't very much.
True, power word kill only works if they're under 60hp, but that's how many they've got at that time. So you could get Firkraag for example down to 59hp and it would kill him instantly. Wish is difficult and I don't like relying on it in the middle of battle. Plus there aren't going to be many times you'll run out of spells in the middle of a battle anyway.
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Goddess and Sorceress of the HADB, and her sidekick Pink