I won the MTGO challenge this past weekend with UWr Stoneblade, 5-1 in swiss. Red still feels like the right choice to me, I believe it has better game vs Delver with its slightly stronger mana base, and while Lightning Bolt can be replaced by Fatal Push for the most part, the sideboard Pyroblasts and Blood Moons give it significant game against some of the tougher matchups in Czech, Miracles, Aggro Loam and other grindy midrange decks. I've always been a big proponent of Pyroblast vs Discard, and while it makes the combo matchup weaker without proactive t1 disruption in Thoughtseize, I have not found myself wanting for more conventional disruption, with 2 Flusterstorm, 3 Hatebears, and the possible 2 RIP and 3 Blast, depending on the type of combo deck, postboard.

I also think that UWr, despite having a 3rd color, is better positioned against Delver than UW, with the additional 1 CMC removal making it easier to keep pace with delver and resolve your bombs without being too far behind on board. the 8 basics were a nod to Delvers primary method of beating us, mana denial; I wanted to be have more chance of simply topdecking basic lands. I almost went with 4 Island 3 plains over the 5 Islands 2 plains, but generally if I can get the basic Island out I can have countermagic to protect from stifle, as well as the obvious cantrips, to protect myself.

List is:

MB
3 Snapcaster
4 Stoneforge Mystice
3 True-Name Nemesis
1 Vendilion Clique

2 Jace, the Mind Sculptor
1 Gideon, Ally of Zendikar

1 Batterskull
1 Umezawa's Jitte
1 Engineered Explosives

4 Brainstorm
4 Swords to Plowshares
4 Force of Will
3 Ponder
2 Counterspell
2 Spell Pierce
2 Lightning Bolt
1 Supreme Verdict

5 Islands
2 Plains
1 Mountain
2 Tundra
2 Volcanic Island
4 Scalding Tarn
4 Flooded Strand
1 Arid Mesa

SB

1 Containment Priest
1 Disenchant
1 Ethersworn Canonist
2 Rest in Peace
2 Flusterstorm
3 Pyroblast
2 Blood Moon
1 Meddling Mage
1 Swords of Fire and Ice
1 Engineered Explosives

My actual matches were

WIN vs DNT
LOSS vs Czech
WIN vs Turbo Depths
WIN vs Maverick
WIN vs BR Reanimator
WIN vs Lands

Top 8

WIN VS DNT
WIN vs 4c Loamd
Win vs Czech

Changes I might make

While I always find myself wanting more cards for whatever matchup I recently played against, you can't have everything, and I try not to get greedy. Having said that, Both my DNT matchups were faily close, and I've had trouble with it in the past. I only have Disenchant and Engineered Explosives to bring in against them, along with Containment Priest as a sort of "why not". 2.5 cards doesn't feel like enough, especially when there were more cards I was willing to side out. I had been thinking about Izzet Staticaster for a long time, as Elves is also a difficult matchup. I also would like to get Council's Judgment back in the 75 somewhere. I was running it, but cut it and the 4th Ponder to make room for the Supreme Verdict and Vendilion Clique. While I do think I want both those cards, I would like the 4th "anti-permenant" card back in the 75, for matchups like DNT but also 4c Loam and other random jank that might just get you with their nonsense. Also a fast LOTV is difficult for this deck.