Caster level -3 for an evocation seems a little small still. I mean when you get fireball at say level 5 youd be doing far more than the equal 2d4 force that meteor would get you.
Edit: Hang on, multiple meteors equal to caster level means you would get 10d4 at level 5 plus knockback. Does the target save for each meteor hitting them?
With that in mind, yes it certainly does provide a nice alternative to fireball.