You've mentioned the problems encountered previously with sets excluding all but 1 card type (I belive it was legions that was only creatures), but what about a set or series of sets that excludes some non creature card type? Creatures already have ETB (and/or dies) effects and activated abilities that mirror a variety of instant/sorcery spells. And we have creatures (like collector oofe) that mirror artifacts (null rod). I'm not asking for or if we should, but more what major problems would have to be addressed?

If a set is optimized by not having something, the possibility exists for us to do it, but it needs to be done to serve the set and not for novelty’s sake.

"I'm not a fan of making cards that don't do anything." But what about Darksteel Relic? Or Null Rod?

Darksteel Relic is the closest to a do nothing card we’ve made. Null Rod stops other things from working, so it clearly has a function. Darksteel Relic’s design was a big debate at the time, but because of affinity for artifacts it at least did something within the environment.

Lord Squishy Asks: Who was overall idea of the Weatherlight Saga? It was our favorite and up until Innistrad none of the other stories had interested us on that same level

The Weatherlight Saga was originally conceived and pitched by myself and my friend Michael Ryan. We were in charge of the story through Stronghold and it got taken away from us during Exodus. One day I’ll write the full story including our original plans for how the story was going to play out. (The Null Rod really was going to be important. And the thing Gerard left behind with his friend did matter.)