it all depends on what kind of style you wish to play im no expert on classes but iv always loved darkknight class, which lead me into the magic classes naming battle mage in particular. its dosent realy have a mage feel to it because of the limited range the battle mage has it feels very much liek a melee class with some preety cool benefits to defense hp and overall survival. my recomendation would be to take ur time and try them out.
Did nexon forget to update there rules before posting a new event i surely hope so and this is just a oversight, It seems strange to me that they would exclude that chunk of the playerbase and if that is not the case then why did they not create a seperate event for EU players? intentionally not giving the same oppertunities to all of your playerbase after pulling off this migration makes me question why do the event in the first place. outraged players unhappy with not being able to participate, people asking questions and im sure some even made tickets expressing there opinion. it not only seems logical and fair to include all your playerbase but it also shows you value the custom of those players. lets hope in the future that nexon gives everyone the same equal oppertunities to participate in events.