Deck has continued to outperform most other decks I have tested against, especially post-sideboard. I have added a few things, and changed a few others, but remained largely consistent on the main deck structure. With that being said, here's my current status.
Bant Harmony vs. UW Spirits: 2-1 One of the worst matchups I've dealt with thus far, and probably the closest matchup. Spell queller eats most of our cards and stuffs some of our ground game. If we can stick a few threats early, they lose most of their advantage. Good matchup to side into Cataclysmic Gearhulk and Avacyn as well as Authority of the Consulate. Authority nullifies the flash ability as blockers, and helps with life gain to offset any tempo advantage they might accrue.
Bant Harmony vs. G/B Delirium: 2-0 What used to be a bad match up is now good. we have enough to stop early game Grim flayers, and they have lost most of their ramp and are substantially slower. Liliana doesn't shoot down our creatures except for Skyspawner, and it's nearly impossible for them to get to Emrakul before we get to panharmonicon. Refector mage and Declaration in Stone are MVPs here. Side in summary dismissal if they drank the Kul-aid, and Quellers or Gideon as well to slow them down early.
Bant Harmony vs. U/R Thermo: 2-1 It's all dependent on their opening few turns game one. We can't race as fast as burn, but we can win easily after siding in quellers and negates. They lack the draw power to keep up with us. Dovin Baan = mvp here providing us life-gain and draw, as well as taking the target off us for a turn or 2.
Bant Harmony vs. R/W vechicles: 2-0 It might be too early in the format to know for sure, and there is probably a better build, but the deck seemed very vulnerable on a number of levels. Sure, on a nut draw it's probably great, but that's most aggro decks. Authority of the Consuls shuts them down, and you can counter the vechicles with negate since they're not creatures when being cast. Focus on removing one or the other and you win easily.