Well they already tried this a few times, I used the Easter even as example but there were more mechanically refreshing events so it prolly is somehow doable but I don't say it isn't more problematic to develop, I agree with you. I don't want them to implement completely new mechanics each event but I would really love to see some more variety from time to time. Anyways I am after wrist surgery and shouldn't be writing that much so I will return tomorrow if there are more replies. ^^
EDIT: Didn't see the innovation you added after you surpassed 1K char limit.
Well, that's the danger of any content, they either have to make balanced content so no one will skip any, force people to do all the ways, implement just one way of obtaining items (which still can be different than stuff that is being added now) or make peace with the fact that some people will choose only the fastest way.