I really think you have something here. I have been testing all day in the MODO Tournament Practice Room and it has been doing a bang up job. The only games I have lost have been due to flood and one odd game with no removal. I apprecaite teh analysis you have written. What I love is the way the deck runs post board against various matchups. The way you can just drop into a control role against a faster aggro deck makes it a lot of fun. I have lost one game today post board against the Golgari decks. I really like this deck and hope something comes of it in standard post rotation. That might be asking too much but it is so much more fun than the R/G Aggro I am running in Standard right now.
I would note that I am not running Godless Shrine in mine,
in favor of two more swamps. Have yet to have an issue with getting RRR for Boros, but oddly enough, there have been a couple times where Ash Zealot didn't come down when I needed her to.
My favorite game, which is one I came out on the loosing end of, was T2 Voice, T3 Voice. Even drawing removal, I couldn't keep up.
In running two Godless Shrine I encountered one game where I could not cast Boros Reckoner for a long time, but it was a game that I was sitting on three land for 8 turns and one of them was a Swamp. Definitely not something that is going to occur often.
Flooding can be a problem with no Rix Maadi Guildmage on board. He's basically the Stonewright of Block Constructed, only much more flexible at the expense of being more mana intensive. I'm actually considering adding a fourth to the sideboard. She's just so good in a lot of matchups.
Golgari is trouble for this deck, but again, postboard makes it much more manageable. This is one of those matches where the
fourth guildmage would be money.
Similarly, GW aggro is a problem for the deck. Voice is impossible for us to deal with profitably, and if they can get a Wurm token out on curve and we have no Dreadbore or guildmage out we have a tough game ahead. Auger Spree is good here to fight Unflinching Courage shenanigans postboard. I also don't mind boarding in Slaughter Games naming Advent of the Wurm. I did this once and it was a game-assuring move.
Compared to Gruul aggro in Standard, I'm inclined to agree that this is more fun to play. I happen to play an 18-land version of Gruul aggro on MTGO and it has a lot of variance. With this deck there are many more keepable hands because the cards are so powerful on their own.
Honestly, after playing many games with this deck, I'm ready to snap up as many extra Exavas, Dreadbores, and Mizzium Mortars I can find. I get the feeling these cards are going to be staples after rotation, especially Exava. She'll basically be the new Falkenrath Aristocrat to
Standard.