I think they should at least consider changing the symbols to make them a little bit more balanced. Some of the symbols are just plain stupid. For example, two of the priest symbols have +attack success rate. Priest doesn't need attack success rate because priest has luck spell, making their attack rate 100% for the duration of the spell. Mage also has two symbols with +attack success rate, and I don't think that's too useful for mages either. Other examples would be BladeSinger and Paladin, they have mana and divine stealing. These are not that great to begin with, and plus I don't think you can still mana or divine if your mana or divine is full.
Also, the amount of effect the symbol should be balanced also. Saint Symbol gives only 19 Nature Vigor, which is not even equal to g2, yet Lord Knight Symbol gives more than G7 Hardest. It's not like priests do a ton of damage with thier spells anyway, except for lifedrain but that isn't effected by Nature Vigor, so it would be nice to get more than a g2 from a symbol.
I'm not sure how accurate the info on this site is, but I remember visiting this site when I played on .my server:
http://www.geocitrus.com/zybyzy/class/symbol.htm