After 20 years, we are probably ripe for a spin-off series or something.
The primary problem with doing Iron DM twice a year is scheduling judges and finding enough competitors. I seem to recall that doing it twice a year made that somewhat harder, though I may be misremembering. A competition which was not elimination, and could be done with only one or two judges would help with that.
I was thinking this morning of trying a summer competition of Iron Ninja DM (name is a work in progress), where contestants were provided ingredients, but then they had to craft a specific sort of thing such as a magic item, an NPC, monster, scenario, that sort of thing, sometimes genre specific, sometimes not. Instead of elimination, assign points and then the one with the most points at the end would be the winner. I can't remember if something like that was already tried a few years ago, but it might be fun to give a go this summer if there is interest.