Well Aeolian is the minor scale so of course it's used more. Ionian is the most used ever. But I left those out for that reason, major and minor. Actually it depends on the type of rock, metal is based mostly in minor but most straight rock songs are major. The major key is alot more 'in your face' sounding, minor is sad and downish sounding. Mixolydian is used in almost all rock styles because of it's bluesy sound (a mix between major and minor in some sense), and you've probably seen the chord bVII a thousand times. The bVII is a good substitute for the viio, which is hardly used.