dont make new mages, make the old ones stronger and de-nerf them. brynhildr is nice but i have NEVER seen her stun more than 2 heroes at once and as said above her damage is insignificant. speaking about it, herja should be able to increase the amount she debuffs morale. this should be done by level and gear. it only makes sense that she gets stronger the more XP she gets. if you think it overpowers her then take into consideration that she doesnt do damage and the opponent can use her as well. she should be able to debuff from 5-30 morale, depending on level and magic attack.
smoulder seems balanced to me and i am sure many will disagree with that, but he turned pvp for me in the past and i cant even count how many times i had only main + smoulder left and still won the fight. the biggest boob or looser as you so want for me is mulan tho. physical resistance on a mage? give her resilience or 50% magic defense, she is a new gold hero and has less magic attack than smoulder... i mean come on, what where you thinking when you made her a tanking mage and her intelligence is even lower than shayds.
instead of inventing new superstrong and OP mages, how about fix the old ones instead and as a start have them miss less?