Dicemanx, did you or your teammates ever consider Abeyance instead of Xantid Swarm? You lose the ability to animate your disruption, which I realize could be a pretty big thing; however, you gain a bigger catchall piece of disruption that can be used to prevent your opponent from winning. It might also gain you some benefits in improper sideboarding from you opponents in those match-ups where it is likely they would be bring in Darkbast or Lava Darts as a way to combat your expected Xantids. I suppose the wishable factor could come up every now and then, though i admit that isn't very likely.
I've used Abeyance before with some success, and Abeyance was a consideration (splashing W instead of G for Xantids) for this deck. We never got a chance to test the SB ideas, but it remains an option. The one downside to Abeyance is the fact that it tacks on an additional 2 mana to an animate spell, and in some instances you don't have that mana to work with. A W splash could also be useful in terms of the addition of Serenity, in part because apparently decks like Stax "crush" WGD as soon as they add 2-3 SB hate cards.
Do you feel that one actual plain isn't enough to support Abeyance? In other words, is there any deck that runs Wastelands in which Xantid Swarms is a key component in your strategy for victory in games two and three? Or do you feel that Abeyance is just inferior to Xantid Swarm for what you want to use it for?
At times I feel that Xantid is inferior even in light of my opponent playing a lot of instant speed disruption, mainly because you really don't want to be cutting the powerful and flexible FoWs and Duresses and you don't want to cut into the combo base too much. How Abeyance will factor into the equation remains to be seen.
My one matchloss all day was against Travis playing Stax. Choke and Null Rod and Needle and Tanglewire were too much for me. So, maybe there is something to this issue of Stax being strong against this build of Dragon.
The way to address those issues is to concede the games where they get overwhelming disruption against you - in the long term, the odds should favor WGD even if in the short term you can get massacred. If you do want to beef up your SB answers though, bounce, Pernicious Deed/EE, and possibly Serenity are your typical options. I disagree that this build is "weaker" than the older builds vs Stax - if anything, its just the opposite. This build has instant speed card drawing (RtR over Compulsion) has more explosive card drawing that doesn't rely on Bazaar (compare DAs vs the largely useless Squees), and has a better disruption base (FoWs and Duresses are better than Xantids and Duresses game 1). We have a low sample size to work with so far regarding the WGD vs Stax match-up, and we cannot get too caught up in the fact that Stax had some measure of success against WGD in 4 matches. Let's see if they can duplicate that feat in 40 matches, or 400 matches.
As for the maindeck, my change was to cut the Entomb for Timewalk. I have a difficult time not playing Timewalk in any deck that resonabley can, as it is at worst a free cantrip. It also accelerates the beatdown plan should it come to that, and it is good for playing around control decks.
Time Walk is marginal in my opinion, but it has its uses to offset its drawbacks. I cannot criticize the choice of including it in WGD, although losing Entomb which can steal so many games when your window of opportunity is at its maximum (the early game) is a pretty tough loss.
Now, onto the sideboard. Xantid Swarm was quite strong. I also had a Tinker in the board as a secondary win condition. This worked pretty well, since it dodges hate and catches people off guard. And although it didn't come up, the fact that their Leyline prevents them from Welding out the creature you Tinker for is nice too. Or maybe I just don't want to stop playing with Tinker.
Tinker is an interesting idea. It makes a lot of sense with the two Titans, and especially as a potential tool to circumvent graveyard hate. I like it.
My concern, however, is the Dragon deck's answer to hate. Tormod's Crypt isn't stopped by Null Rod or Pithing Needle, since your opponent can just wait until the Null Rod or Needle flickers out and then get you. Null Rod only stops people from Crypting you when they forget how Dragon works, and I'd certainly want something better than that.
My game 2 answer to hate is typically 2-3 bounce spells, followed by a modification in game 3 if necessary once I have a better idea of what exactly I'm up against. Sometimes I might bring in Xantids/EE/Deeds if I'm aware of my opponent's SB strategy. And while Rods don't answer Crypt, there are other ways to address the card - Scott already outlined some of these. Necromancy, bounce, baiting with a WGD or Titan are just some of the ways. Others include pre-emptive CotVs for 0, Deed/EE, or Serenity again if the W splash is considered. I don't sweat it too much, because while hate stops the combo, it doesn't stop mana development and card drawing, and your main plan might be to simply outdraw your opponent, Duress/FoW his threats, and power past the hate like Crypt.
There is one additional possibility which still remains relatively unexplored - the transformational SB which avoids the use of the graveyard. I've tried this exactly once almost a year ago (using a Mask/Dreadnaught/Survival of the Fittest/Carpet of Flowers/CotV SB in 5CWGD). While I didn't get a chance to consider such options here, they are always on the radar for me as far as constructing this deck is concerned. There are so many options that i wish I had more time to explore, but I feel fortunate that the version we brought to Rochester was more than up to the task.