I caught a level twelve gobball when I was level two because the AI is reallly that stoopid. However, the gobball become Lv 2 as well due to limits. Leveling Seduction is the only hampering toward summoning because it becomes really hard to level compared to other spells and the only way to get the second monster slot is to get it to level twenty five.
Earth Osa is the only path toward dependable soloing without counting on summons. However, it's first spell is really horrible.