Excellent idea. There are a lot of people who suffer at this, simply because they have to meet the demands of life.
How about a Banish Event every 6 hours? Different god/demon with different drops. Randomized or Cycled bosses, so that ppl aren't always fighting the same guy?
Lastly - World Bosses are fun, but it is REALLY tough to get anything back from your efforts, unless you're already a god... how about randomly dropping a gem or a Level 5 to Level 15 Apprentice gear (chance based)?