3.5 - Wizard level 1 spell selection advice

[Eloel]

Power Word: Pain?

The first level spell that damages like a 2-4th level spell.

That spell is weird actually. It gets less effective quadratically as you level up, instead of the usual "get more effective quadratically". You get lowered duration with enemy's HP going up AND the enemy's hp goes up. Vs someone with, say, 40 hp, you deal 10d6 average. Vs someone with 80 hp, you deal 5d6 average. Double the hp, half the damage, it becomes useless in time.