If you are only going to dual box 1 support class I would suggest the SE because what you are going to need more than anything else as a Spellhowler is extra MP which only the SE or EE could provide you however the SE also has buffs that will assist you more so than the EE's buffs would. As far as prophet goes. Back in the day the prophet was the most important support class in the game but now they are practically useless because you have the buff scrolls that provide most of the important buffs for you for cheap. So focusing on a support class that can recharge your MP quickly is the most important thing to consider.
