The cheaper costs and increased inspiration would be better once you already have the character made, right? You realize that this next DLC is only the dungeons; we're not getting the Arcanist class until June when Necrom drops. Why would we want our levelling event to happen before we can make the characters?
Zeal isn't a leveling event, it is a crafting event, and amongst the rewards are mount training tomes and companion gear. I would rather have those ready when Necrom drops with my new character that needs gear for 2 new companions and 6 months worth of mount training. Cheaper teleports to wayshrines the new character hasn't found yet and 1/2 off houses that are account wide don't seem that worthwhile by comparison. I guess if someone is masochistic enough to want to make a new Arcanist their crafting main it would benefit them slightly to have the event come out after Necrom drops.