Why are the "weird and wordy red enchantments" like Warp World, Sun Bird's Invocation, Form of the Dinosaur, Guild Feud and Haphazard Bombardment rare instead of Mythic? Thanks for answering our questions sir.

Cards that are complex and/or very niche oriented are put at rare rather than mythic rare which tends to get the more splashy effects.

Is there someone in development who answers questions like you do, or where should we ask questions that relate to manacost/power level? (In case you feel up to answering, the question is why some interesting and otherwise reasonable build-around cards are overcosted to the point of nigh-unplayability, even in limited. Notably Guild Feud feels very overcosted.)

No one in development is doing anything like this blog. Actually no one at Wizards is doing anything like this blog.  Note that not every card is pushed. Some cards are costed for more casual and thus more forgiving formats that allow players to get to higher mana costs more easily.

Hi, Mark. RTR spoilers are going great. The set looks awesome. I especially like the one-drop hybrids we've seen so far. Slitherhead is terrific! One thing, tho. I thought after Knowledge Pool you guys were trying to avoid really convoluted cards. What's up with Guild Feud? That thing is mind boggling. Does RnD still like cards with that many steps to resolve?

New World Order doesn’t mean the game can’t have some complicated cards. We just put them at a higher rarity. Magic should have some cards with rules text in a tiny font.