I feel the event has a nice win-win with this Infernal Carnival of Nightmares theme with both Jack and Oddfellow. Since you not only have Jack, but Dr. Oddfellow who's honestly the best new Icon they've had in a while. It's probably a boon to marketing etc. that Oddfellow is directly tied to Jack, so it's an easy-peasy way to bring both Icons of Old and New together.
When it comes to the other Icons, I would love to see the Caretaker return in some fashion in the future. His concept and motivations are very easy to understand, and he's just wonderfully unsettling. It also doesn't hurt Screamhouse has been a solid set of houses. If they roll with another gothic/haunting kind of feel, he's perfect for that.
As for the others, they'd be nice to see in a main anniversary year, but I'm not necessarily clamoring for them. One of the best examples of that is Fear, where I couldn't help but notice he wasn't in the slideshow of Icons at Megacon. They showed Lady Luck who came after him, but not him and I feel that's pretty telling.
No, they're not saving him up for later, he's just been immensely half-baked. After all, he never was the intended Icon for XX, that was Cindy of course. And his gimmick of being this master of fear, behind all the monsters and so forth...has been retconned and taken over by Dr. Oddfellow who is actually fleshed out and just a better Icon, period.